Got a few questions.

1). Where is the oil pressure sending unit on the 2.8? (A pic would be great!)

2). Where can I get new exhaust manifolds and y-pipe (stock and/or emisssions legal)?

3.) How much would a shop charge (guesses) to install items in question 2?

 

1. No pic, but look above your oil filter. There's two pressure sensors. One of them has two wires; that's the "fuel pump safety switch" oil pressure sensor. The sensor with one tan wire is the oil pressure sensor for the dash gauges. Note that later models, seemingly, 88-and-up, use one LARGE sensor for both functions.

2. New? You can buy a new y-pipe. I bought mine from a "real" auto parts store (not Pep Boys/AutoZone/etc)... one of those local joints. It cost me $180 back in 1996, was made by AP, and as a surprise, was mandrel-bent. I don't think you'll find new exhaust manifolds... but the junkyards are full of 'em. Find a junkyard that can cut the old y-pipe off with a torch, because it's a btch to get a wrench in there to loosen the manifold-to-y-pipe nuts... especially if the car has no wheels and is sitting in the mud.

3. Installation should be $0, because you can do it yourself easily. Buy new bolts. I have a message up somewhere in the V6 forum (do a search) on the exact bolt sizes for the exhaust-manifold-to-head.

 

It is a real pain to do the exhaust manifolds. All the bolts are ten mm. Bottom studs for pipes are 15mm. I am not saying it cannot be done, tho. But it is a pain!
I went to the yard and got a spare exhaust manifold set. THEY WERE ON THE GROUND!! Make sure you have those manifolds checked for flat surface!!!!! "Y" pipe, go high performance! Have it made!! You'll gain 5-10 HP with this mod & new style Cat Convertor.
Call Don't Hot Rod 800-888-8892 for the parts. Should set ya back about $175. Install$$? That's your call. I'd shop around for a real artist bender, tho