Single Exhaust to Dual Exhaust on my box....Looking for advice

[BoxChevyUC]

Anyone have any experience in the exhaust switch......I have a 1990 Box caprice with a 305cid, V8 Police Package......Any ideas?

[HuSSker]

I'm slowly in the process of doing this too on my '79 2 door. Here's what I've done so far:

For the clearance in the transmission area, I got a cross member off of a '95 9C1, as they have 2 humps on them to clear the pipes, and bolted right into my '79 with no modifications to the crossmember itself. I did however have to make a 6" extension on the passenger side mount on the frame of the car, allowing the crossmember to be mounted more rearward, as it is on the '94-'96, which was VERY easy. Secondly, in order to use the crossmember, your 4L60 transmission will need a tailshaft housing that has a transmission mount on it. They are somewhat rare, but they're out there. I also got the exhaust hangers off of the '95, and plan to mount them when the exhaust goes in. Using this method, I will be able to choose from a variety of cat-backs that are availible for the '94-'96 Caprice/Impala SS. As far as the cat-forward goes, you could do a few things: different types of headers, stock manifolds/cats off of a '94-'96 Caprice/Impala SS, or have your local exhaust shop fabricate something. Of course there's a few small details in between all of that, but that's the basic rundown. On my setup, so far, so good. Best of all, everything I've done came out of the salvage yard, and has only cost me about $30, and looks stock.

Sorry for the long post, I hope this helps.