Replacement large power input plug for select HD and MHD Amplifiers:

Fits the following models only:
HD750/1 (excluding HD750/1 with Serial Numbers < #108034000001, which use )
HD1200/1
MHD750/1 (excluding MHD750/1 with Serial Numbers < #153034000001, which use )

Corresponding plug shroud on applicable amplifiers does not have phillips head screws.

Need additional information on selecting the correct plug?