I was looking at a BC-312, nameplate gone, it has these stamps: MWO SIG-11-850-1-3 MWO SIG-27 C-1 MFP 8-51 SPEC MOD The noise antenna hole has a hole plug. There is a hole below the bandswitch, also hole plugged. There are no watcholder screw holes. So what is the " SPEC MOD " ? thanks- Hue Miller