diff --git a/examples/cfg/xcorev/XCoreVAlu.yml b/examples/cfg/xcorev/XCoreVAlu.yml
index 69f49a18..c900d667 100644
--- a/examples/cfg/xcorev/XCoreVAlu.yml
+++ b/examples/cfg/xcorev/XCoreVAlu.yml
@@ -8,7 +8,7 @@ extensions:
     vendor: true
 passes:
   per_model:
-    XCoreVMac:
+    XCoreVAlu:
       overrides:
         convert_models:
-          prefix: "SEAL5"
+          prefix: "SEAL5_"
diff --git a/examples/cfg/xcorev/XCoreVBitmanip.yml b/examples/cfg/xcorev/XCoreVBitmanip.yml
index 8bd660c8..661e1f1f 100644
--- a/examples/cfg/xcorev/XCoreVBitmanip.yml
+++ b/examples/cfg/xcorev/XCoreVBitmanip.yml
@@ -8,7 +8,7 @@ extensions:
     vendor: true
 passes:
   per_model:
-    XCoreVMac:
+    XCoreVBitmanip:
       overrides:
         convert_models:
-          prefix: "SEAL5"
+          prefix: "SEAL5_"
diff --git a/examples/cfg/xcorev/XCoreVBranchImmediate.yml b/examples/cfg/xcorev/XCoreVBranchImmediate.yml
index 899c06ff..906fcf0d 100644
--- a/examples/cfg/xcorev/XCoreVBranchImmediate.yml
+++ b/examples/cfg/xcorev/XCoreVBranchImmediate.yml
@@ -8,7 +8,7 @@ extensions:
     vendor: true
 passes:
   per_model:
-    XCoreVMac:
+    XCoreVBranchImmediate:
       overrides:
         convert_models:
-          prefix: "SEAL5"
+          prefix: "SEAL5_"
diff --git a/examples/cfg/xcorev/XCoreVMac.yml b/examples/cfg/xcorev/XCoreVMac.yml
index 4aa6b9da..71f5b714 100644
--- a/examples/cfg/xcorev/XCoreVMac.yml
+++ b/examples/cfg/xcorev/XCoreVMac.yml
@@ -11,4 +11,4 @@ passes:
     XCoreVMac:
       overrides:
         convert_models:
-          prefix: "SEAL5"
+          prefix: "SEAL5_"
diff --git a/examples/cfg/xcorev/XCoreVMem.yml b/examples/cfg/xcorev/XCoreVMem.yml
index 35b205a0..0549417f 100644
--- a/examples/cfg/xcorev/XCoreVMem.yml
+++ b/examples/cfg/xcorev/XCoreVMem.yml
@@ -8,7 +8,7 @@ extensions:
     vendor: true
 passes:
   per_model:
-    XCoreVMac:
+    XCoreVMem:
       overrides:
         convert_models:
-          prefix: "SEAL5"
+          prefix: "SEAL5_"
diff --git a/examples/cfg/xcorev/XCoreVSimd.yml b/examples/cfg/xcorev/XCoreVSimd.yml
index 084d4707..fe71357e 100644
--- a/examples/cfg/xcorev/XCoreVSimd.yml
+++ b/examples/cfg/xcorev/XCoreVSimd.yml
@@ -8,7 +8,7 @@ extensions:
     vendor: true
 passes:
   per_model:
-    XCoreVMac:
+    XCoreVSimd:
       overrides:
         convert_models:
-          prefix: "SEAL5"
+          prefix: "SEAL5_"
diff --git a/seal5/transform/converter.py b/seal5/transform/converter.py
index 861f3568..372ff48c 100644
--- a/seal5/transform/converter.py
+++ b/seal5/transform/converter.py
@@ -67,8 +67,9 @@ def main():
         logger.info("replacing set %s", set_name)
         for enc, instr_def in set_def.instructions.items():
             if args.prefix:
-                instr_def.name = f"{args.prefix.upper()}_{instr_def.name}"
-                instr_def.mnemonic = f"{args.prefix.lower()}.{instr_def.mnemonic}"
+                instr_def.name = f"{args.prefix.upper()}{instr_def.name}"
+                prefix_ = args.prefix.lower().replace("_", ".")
+                instr_def.mnemonic = f"{prefix_}.{instr_def.mnemonic}"
             set_def.instructions[enc] = seal5_model.Seal5Instruction(
                 instr_def.name,
                 instr_def.attributes,