Was interested in finding out if anyone here is using these particular headers on their 3rd gen Formulas (or any 3rd gen for that matter). The design is such that it actually follows the factory routing to connect to the factory style exhaust with the collectors making the proper turns to the passenger side of the car. You'd just need to find a muffler shop to fabricate the Y pipe for connection to the cat/cats and exhaust. They also appear to be perfect for 305s (and some 350 combos for that matter) with 1.5" primaries and 2.5" collectors with AIR and O2 provisions optional. I read an article several years ago in PHR I think where GMPP took the 25th Anniversary Camaro that never made it to production and did an LT1 install using these same headers and it made some impressive numbers. I know this statement is going to draw fire but with these longtube headers out there and their obvious improvement in ground clearance compared to traditional longtubes, why isn't anyone using them? I've known about them for several years but when I found out about them I already had Edelbrocks in the car but have always had them on the "needed parts list" when I build a motor for the car (a 305 in case you ask, just to be a bit different). If anyone here has them in service let me know how they're doing for you. If anyone is interested in seeing them just go to Summit Racing and type in the part number, look at the coated version as that's the actual parts, the painted ones show a different set for representation only. They are a bit pricey but look to be worth it for longtubes AND ground clearance.

Is your bird a standard or automatic trans?
If its standard / manual do you have a hydrolic clutch?
If its a manual with hyd it should fit ok but i would wrap the clutch hyd hole with fiberglass tape and aluminum shielding to prevent the fluid from getting too hot.
If its a manual with a z bar the headers may be hard to fit.

I have run into this with my 2nd gen - it has a z bar to push the clutch in
My 02 Z28 has hydrolics and the fluid boiled killing the master
My 00 Formie has an automatic with Hookers and there have been no problems

Mine's an auto. I spoke with a tech at Hooker yesterday and the only real concerns were making the connections to the rest of the exhaust and the potential for ground clearance problems on lowered cars with the primaries actually being in the turn going underneath the car to the passenger side.