If you're working on an A-body you will want either Doug's headers or TTi. These are the only two that fit and don't scrap the ground (the Doug's are 1 5/8, while the TTi's are step headers going from 1 5/8 to 1 3/4).
O a truck. Well lot more room for headers then. Had a set of hookers I keep in my 360 76 Dodge truck. Had headers on it to but don't remember what brand.
always loved my hookers good fit strongley built and a thick flange i never had a leak with hookers at the flange or collector put them on in 97 and still going strong