Clean-slate exhaust--What am I missing?

My car has nothing after the badly-corroded cast iron exhaust manifolds. My plan is to use the Summit brand 2 1/4" dual kit for the firebird SUM-680100 (http://store.summitracing.com/partdetail.asp?autofilter=1&part=SUM%2D680100&N=700+4294908153+4294907958+4294925083+4294920008+ 115&autoview=sku). The kit was designed to work with"Hooker headers where they do not exit parallel and at the same distance". So I thought, why not upgrade now to LT headers by hooker, for easier installation? HOK-4902HKR (http://store.summitracing.com/partdetail.asp?part=HOK%2D4902HKR&view=1&N=700+). Looking at these parts/kits, is there anything I'm missing? If anyone has had any experience w/ either of these kits, your opinion is greatly appreciated. Thanks