I am trying to remove the Powerhead from Exhaust Assembly on a 4W75A (which runs great has Transom Clamp broken, badly eroded paint etc.on lower unit) to install on a near-pristine (except blown cylinder/crankcase!) 4R76M. Crankshaft and all other necessary mating parts are identical between the 2 engines (Flywheels and other non-mating parts are different--I know). I have completely disassembled the recipient 4R76M so I am quite familiar with how it is configured. But I am stuck on what should be an easy step! I removed the 6 bolts which hold the 4W75A Powerhead to the Lower Cover 0388044 and Exhaust Housing 0314813. On the 4W75A I can raise the Powerhead/LowerCover about 1/8inch from the Exhaust Housing 0314813 but get a lot of resistance lifting further. The Gasket 0315338 has separated cleanly from the Exhaust Housing, i.e. stayed with the Lower Cover. So I don't have a gasket (with gasket compound etc) holding things together. Could the copper cooling pipe be stuck in the rubber bushing in the bottom of lower unit near impeller? Could I cause any damage by "brute forcing" the Powehead/LowerCover apart from the Exhaust Housing? Any help would be appreciated...