More POWER!

I have a 91 Silver. with the 4.3 ltr and the 5 speed manuel tranny. I am wondering if I can bolt a 305 or 350 to the existing tranny and mounts. I figure I would run a self contained ignition and a nice four barrel Holley, bypassing the computer and emmisions. The 4.3 runs great but lacks the power I need to tow a 14' trailer.Thanks for the advise.

Bellhousing mount pattern is same on 4.3, 305, and 350. Motor mounts are different.Junkyard has correct ones. Will run with same computer. Runs better with 305 or 350 computer. Lots of work, but cheap if you do it yourself--Free labor.