Been debating on new headers since mine are fairly rusty and have already done full exhauts from the catalytic converter back. Found a set of full lenth headmen's headers on summit for about $200 shipped. I know bolting up the new headers good and using Cooper seal on the ball mount where the headers meet the y pipe is important to prevent leeks. Also that mods to the y pipe and exhaust have to be made to keep the catalytic converter, also fine with that.

But the instructions they had a link to talked about removing pulleys from the engine and removing the starter and all kinds of stuff. Is this all neccesary? I figured it would be a pretty straight foreward thing to do. I'm gonna have my mechanic tackle the job for me, but was just wondering what all is involves before I fully dedicate to it.

 

well the 350 headers wrap around the steering shaft, so that has to come out. And its pretty tight in there with either engine, so I wouldnt be surprised if a couple things have to come off to get them to slide in. Since the 4.3 and 5.7 are the same width, Im guessing that the 4.3 headers would also have to wrap around the steering shaft and would be hard to get in. My truck as ABS and there is a bunch of that stuff in the way too. the headers on my 350 S10 went in on the engine, and I can imagine trying to get them off when the engines in the truck... So yeah I imagine your mechanic is right that some stuff has to come off.