diff --git a/bin/wsim b/bin/wsim
index 9884992e4..db9b53258 100755
--- a/bin/wsim
+++ b/bin/wsim
@@ -14,38 +14,16 @@
 import argparse
 import os
 
-def LaunchSim(ElfFile):
-    # Launch selected simulator
+
+def LaunchSim(ElfFile, flags):
     cd = "cd $WALLY/sim/" +args.sim
-    # ugh.  can't have more than 9 arguments passed to vsim. why? I'll have to remove --lockstep when running
-    # functional coverage and imply it.
+
+    # per-simulator launch
     if (args.sim == "questa"):
-        if (args.lockstep):
-            prefix = "IMPERAS_TOOLS=" + WALLY + "/sim/imperas.ic"
-            if(int(args.locksteplog) >= 1): EnableLog = 1
-            else: EnableLog = 0
-            if(args.locksteplog != 0): ImperasPlusArgs = " +IDV_TRACE2LOG=" + str(EnableLog) + " +IDV_TRACE2LOG_AFTER=" + str(args.locksteplog) 
-            else: ImperasPlusArgs = ""
-            if(args.fcov):
-                CovEnableStr = "1" if int(args.covlog) > 0  else "0";
-                if(args.covlog >= 1): EnableLog = 1
-                else: EnableLog = 0
-                ImperasPlusArgs = " +IDV_TRACE2COV=" + str(EnableLog) + " +TRACE2LOG_AFTER=" + str(args.covlog) + " +TRACE2COV_ENABLE=" + CovEnableStr;
-                suffix = ""
-            else:
-                CovEnableStr = ""
-                suffix = "--lockstep"
-        else:
-            prefix = ""
-            ImperasPlusArgs = ""
-            suffix = ""
+        # Questa cannot accept more than 9 arguments.  fcov implies lockstep
         if (args.tb == "testbench_fp"):
             args.args = " -GTEST=\"" + args.testsuite + "\" " + args.args
-        cmd = "do wally.do " + args.config + " " + args.testsuite + " " + args.tb + " " + args.args + " " + ElfFile + " " + suffix + " " + ImperasPlusArgs
-        if (args.coverage):
-            cmd += " --coverage"
-        if (args.fcov):
-            cmd += " --fcov"
+        cmd = "do wally.do " + args.config + " " + args.testsuite + " " + args.tb + " " + args.args + " " + ElfFile + " " + suffix + " " + flags
         if (args.gui):  # launch Questa with GUI; add +acc to keep variables accessible
             if(args.tb == "testbench"): 
                 cmd = cd + "; " + prefix + " vsim -do \"" + cmd + " +acc -GDEBUG=1\""
@@ -58,24 +36,20 @@ def LaunchSim(ElfFile):
     elif (args.sim == "verilator"):
         # PWD=${WALLY}/sim CONFIG=rv64gc TESTSUITE=arch64i
         print(f"Running Verilator on {args.config} {args.testsuite}")
-        if (args.coverage):
-            print("Coverage option not available for Verilator")
-            exit(1)
-        if (args.gui):
-            print("GUI option not available for Verilator")
-            exit(1)
         os.system(f"/usr/bin/make -C {regressionDir}/verilator WALLYCONF={args.config} TEST={args.testsuite} TESTBENCH={args.tb} EXTRA_ARGS='{args.args}'")
     elif (args.sim == "vcs"):
         print(f"Running VCS on " + args.config + " " + args.testsuite)
         if (args.gui):  
             args.args += "gui"
-        elif (args.coverage):
-            args.args += "coverage"
-        cmd = cd + "; ./run_vcs " + args.config + " " + args.testsuite + " " + args.args
+        cmd = cd + "; ./run_vcs " + args.config + " " + args.testsuite + " " + args.args + " " + flags
         print(cmd)
         os.system(cmd)
 
 
+########################
+# main wsim script
+########################
+
 # Parse arguments
 parser = argparse.ArgumentParser()
 parser.add_argument("config", help="Configuration file")
@@ -96,6 +70,7 @@ print("Config=" + args.config + " tests=" + args.testsuite + " sim=" + args.sim
 ElfFile=""
 DirectorMode = 0
 ElfList = []
+WALLY = os.environ.get('WALLY')
 
 if(os.path.isfile(args.testsuite)):
     ElfFile = "+ElfFile=" + args.testsuite
@@ -111,21 +86,43 @@ elif(os.path.isdir(args.testsuite)):
 print(ElfList)
 
 # Validate arguments
-if (args.gui):
+if (args.gui or args.coverage or args.fcov or args.lockstep):
     if args.sim not in ["questa", "vcs"]:
-        print("GUI option only supported for Questa and VCS")
-        exit(1)
-
-if (args.coverage):
-    if args.sim not in ["questa", "vcs"]:
-        print("Coverage option only available for Questa and VCS")
+        print("Option only supported for Questa and VCS")
         exit(1)
 
 if (args.vcd):
     args.args += " -DMAKEVCD=1"
 
+# if lockstep is enabled, then we need to pass the Imperas lockstep arguments
+if(int(args.locksteplog) >= 1): EnableLog = 1
+else: EnableLog = 0
+if (args.lockstep):
+    prefix = "IMPERAS_TOOLS=" + WALLY + "/sim/imperas.ic"
+    if(args.locksteplog != 0): ImperasPlusArgs = " +IDV_TRACE2LOG=" + str(EnableLog) + " +IDV_TRACE2LOG_AFTER=" + str(args.locksteplog) 
+    else: ImperasPlusArgs = ""
+    if(args.fcov):
+        CovEnableStr = "1" if int(args.covlog) > 0  else "0";
+        if(args.covlog >= 1): EnableLog = 1
+        else: EnableLog = 0
+        ImperasPlusArgs = " +IDV_TRACE2COV=" + str(EnableLog) + " +TRACE2LOG_AFTER=" + str(args.covlog) + " +TRACE2COV_ENABLE=" + CovEnableStr;
+        suffix = ""
+    else:
+        CovEnableStr = ""
+        suffix = "--lockstep"
+else:
+    prefix = ""
+    ImperasPlusArgs = ""
+    suffix = ""
+flags = ImperasPlusArgs 
+
+# other flags
+if (args.coverage):
+    flags += " --coverage"
+if (args.fcov):
+    flags += " --fcov"
+
 #  create the output sub-directories.
-WALLY = os.environ.get('WALLY')
 regressionDir = WALLY + '/sim/'
 for d in ["logs", "wkdir", "cov"]:
     try:
@@ -135,7 +132,7 @@ for d in ["logs", "wkdir", "cov"]:
         
 if(DirectorMode):
     for ElfFile in ElfList:
-        LaunchSim(ElfFile)
+        LaunchSim(ElfFile, flags)
 
 else:
-    LaunchSim(ElfFile)
+    LaunchSim(ElfFile, flags)
diff --git a/sim/vcs/run_vcs b/sim/vcs/run_vcs
index 80385f6ba..d9d53e45b 100755
--- a/sim/vcs/run_vcs
+++ b/sim/vcs/run_vcs
@@ -92,24 +92,22 @@ RTL_FILES="$INCLUDE_DIRS $(find ${SRC} -name "*.sv" ! -path "${SRC}/generic/mem/
 OUTPUT="sim_out"
 VCS_CMD="vcs +lint=all,noGCWM,noUI,noSVA-UA,noIDTS,noNS,noULCO,noCAWM-L,noWMIA-L,noSV-PIU,noSTASKW_CO,noSTASKW_CO1,noSTASKW_RMCOF +vcs+vcdpluson -suppress +warn -sverilog +vc -Mupdate -line -full64 -kdb -lca -debug_access+all+reverse  -ntb_opts sensitive_dyn ${INCLUDE_PATH} $RTL_FILES"
 SIMV_CMD="./${WKDIR}/$OUTPUT +TEST=${TESTSUITE} ${PLUSARGS}" 
-COV_FILES="${TB}/coverage/test_pmp_coverage.sv"
-COV_OPTIONS="-cm line+cond+branch+fsm+tgl -cm_log ${WKDIR}/coverage.log -cm_dir ${WKDIR}/COVERAGE"
-### CODE COVERAGE REPORT in IndividualCovReport in XML format
-#COV_RUN="urg -dir ${WKDIR}/COVERAGE.vdb -report IndividualCovReport/${CONFIG_VARIANT}_${TESTSUITE}" 
-### CODE COVERAGE REPORT in IndividualCovReport in text format
-COV_RUN="urg -dir ./${WKDIR}/COVERAGE.vdb -format text -report IndividualCovReport/${CONFIG_VARIANT}_${TESTSUITE}"
-
 
 # Clean and run simulation with VCS
 
-if [ "$3" = "coverage" ]; then
+if [ "$3" = "--coverage" ]; then
     echo -e "${YELLOW}#### Running VCS Simulation with Coverage ####${NC}"
-    # Code Coverage.
+    COV_OPTIONS="-cm line+cond+branch+fsm+tgl -cm_log ${WKDIR}/coverage.log -cm_dir ${WKDIR}/COVERAGE"
+    COV_RUN="urg -dir ./${WKDIR}/COVERAGE.vdb -format text -report IndividualCovReport/${CONFIG_VARIANT}_${TESTSUITE}"
     $VCS_CMD -Mdir=${WKDIR} $COV_OPTIONS -o ${WKDIR}/$OUTPUT -Mlib ${WKDIR} -work ${WKDIR} -l "$LOGS/${CONFIG_VARIANT}_${TESTSUITE}.log"
-    $SIMV_CMD $COV_OPTIONS
+    $SIMV_CMD $COV_OPTIONS # dh 6/27/24 *** are COV_OPTIONS really needed?
     $COV_RUN
     #cp -rf urgReport $COV
-
+elif [ "$3" = "--lockstep" ]; then
+    echo -e "${YELLOW}#### Running VCS Simulation with Lockstep ####${NC}"
+    LOCKSTEPVOPTSTRING=" +define+USE_IMPERAS_DV +incdir+$env(IMPERAS_HOME)/ImpPublic/include/host  +incdir+$env(IMPERAS_HOME)/ImpProprietary/include/host  ${IMPERAS_HOME}/ImpPublic/source/host/rvvi/*.sv ${IMPERAS_HOME}/ImpProprietary/source/host/idv/*.sv -sv_lib ${IMPERAS_HOME}/lib/Linux64/ImperasLib/imperas.com/verification/riscv/1.0/model "
+    $VCS_CMD -Mdir=${WKDIR} $LOCKSTEP_OPTIONS -o ${WKDIR}/$OUTPUT -Mlib ${WKDIR} -work ${WKDIR} -l "$LOGS/${CONFIG_VARIANT}_${TESTSUITE}.log"
+    $SIMV_CMD 
 else
     echo -e "${YELLOW}#### Running VCS Simulation ####${NC}"
     $VCS_CMD -Mdir=${WKDIR} -o ${WKDIR}/$OUTPUT -work ${WKDIR} -Mlib ${WKDIR} -l "$LOGS/${CONFIG_VARIANT}_${TESTSUITE}.log"