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Depending on the shape of the crank, you can have it cut down. new rods, pistons, rings, bearings, oil pump.. the whole 9 yards. it can easily be done for under 5k.
As stated just make sure you do all the preliminary precautions when installing and opti and you should be fine.
P.s. there's more to an LS1 swap than just the motor and pcm. You have to change the k member, trans, exhaust, etc. When it comes down to money, it's cheaper to rebuild the LT1. Yes the LS1 is a better option, but it's more work and much more expensive.

