if i drop a v8 can i use the same trans from my 4.3 v6

 

yeah the SBC and 4.3 use the same bellhousing pattern

 

what about the computer and stuff

 

Well, any swap would need to have the PCM upgraded... That is unless you are going from a TBI 4.3L to a TBI 350. If that was the case, then I think that many have been plug-n-play. For a CPI to v8 application, you would need some pretty good modification of not only the wiring, but the PCM as well. For the SCFI 4.3L (96+), you're looking at a bit of wiring, then just flash the v8 engine management software to your PCM and drop in a SCFI 5.7L v8 (which is what I am currently hunting parts for).