I have a 2000 chevy silverado with a 4.3 V6 and I plan to swap it with a 350 real soon. So I asked a guy at a local performance shop if I have to change the tranny also. He said it should bolt right onto the 350. So I just to be sure I wanted to ask yall if he's right or wrong. anyone please help me on this issue, i would really like that

 

Yep it will bolt right up, I've been told it's the same block just missing two cylinders lol..