Lets say I buy a short block from http://www.victoryracingengines.com/...TX&BLOCK=SHORT

or http://www.golenengineservice.com/html/lt1_lt4.html

will I be able to take off the part from my current LT1 and use it on the short blocks? Also, is that all I need to buy, a short block or would I need to buy some more stuff like MSD Opit or something else?

Thanks