Inliners International Forums General Discussion Engines Where to find piston and rods for 270 GMC

I really want to keep it original as a 59 GMC Ive also thought about tracking down a 336 GMC to put in. The truck actually has a pretty good running 62 235 that needs some carb work and a rear main seal pretty bad. Is there a way to put a rear main in without pulling the engine?