Headers are usually always a pain.... i picked up a set of hookers i think, second hand at a swap meet in bowling green some 20 years ago it seems, at one of the NCM functions.... 35 dollars, installed them on dad's 76... the exhaust is straight piped so emissions isn't a concern. I can't see how the A/C bracket would be a problem, it shouldn't attach to the stock manifold, but i could be wrong..... biggest issue we had getting them installed was that on the driver side(if i remember correctly) we had to remove the motor mount bolt and jack the engine up a little to wiggle it down in there... the only other issue is if you need to pull your starter off, you will most likely have to remove the header or at very least loosen up everything to remove / install the starter....
given the little room under the hood of these c3's... do make sure the headers you have are vehicle specific...looked up your part number and what few reviews i saw, they were also having problems fitting them on.... so there might be a manufacturing problem with the Heidmans....
As for headers for a '74 for your car, they "should" work.... if they were previously installed without any issues, then you "should be" ok.... realize the quotes, as you milage may vary.
Looking up Dougs D350 headers, they seem to have a lot better reviews.... best reason i can think of why they stop at 1974 is for emissions... most places that have emission testings don't like/approve exhaust modifications on vehicles prior to 1975-ish. If you are in an area that doesn't require emission/inspections then probably no worries...
oh, copper gaskets, i highly recommend them... major pain having to replace the fiber/paper gaskets every year or sooner.... :)
hope that helps a little....
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StingrayJim
NCM Lifetime Member #1936
Stingray's '76���������������������������� StingrayJr's '78���������������������������Lil Red '94
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