Bruce 88123,when you say the engine is locked up,do you mean locked up due to a congealed or hardened varnish build up(burnt oil residue etc.) or is it due to rust?I don't know if you necessarily have to rip the engine all apart just to free it up if that's all your trying to do.The engine can be soaked/cleaned in one piece in a crock pot of anti-freeze to free up the engine and remove the congealed residue.I would remove the engines back plate though to allow the hot anti-freeze to penetrate more efficiently internally.If your trying to assess the bearings individually, then yes your going to have to remove the crank from the engine to do this.Unless the bearings felt rough and ratchety turning the crank slowly or looked rusted,I wouldn't bother with them now until after I cleaned up the engine first.You may be changing the bearings uneccessarily.Just my 2 cents worth.Good luck with the engine.