Take a picture of the existing accessory bracket so we can be sure of what is in the car so we can be better prepared to help you. Stating what you "should" need is easy, nobody can state what you do need till we know what you have, especially when the car has been bastardized already. Please don't take that as a cut against using a b-body motor, that is a perfectly reasonable option for the repair you seek.

 

I just pulled a good running shortblock out of my 97 this weekend. Pm me if interested

 

Yeah, the 4.3 can be a nasty surprise if your are expecting a 5.7.....that's why I was wondering how he knows it's a 4.3. I never knew they existed, until I read a thread where a guy was really down on power(installed a used motor) and no one was sure why until they tore the motor down and found the reduced bore and stroke. From my understanding, there was no real tell from looking at the front and sides of the block.

I've seen some references say you can tell by looking a the back of the block, but I'm not sure.