If you are looking to upgrade your engine hp's, you can have the block bored out at your local machine shop. If there was a crack or something wrong with the block, they would be able to diagnos it for you. You can also have the shop work the heads over as well. Then order all of your parts through enginebuilders. This should save you quite a lot of money over ordering a complete engine from either DOA or LCE, their engines are nice but pricey.

More than tread lightly. Leave it like you were never there, nor anyone else.
'90 X-cab 4.88's 33 BFG AT's, rr ARB, Headers, Ignition upgrade, cold air induction.
'91 X-cab 5.29's 315's BFG MT's, rr ARB, custom bumper and flatbed