You are quickly going to find very enthusiastic recommendations for Ram Air style long branch exhaust manifolds that many others have found to have eliminated many of the header pains you are talking about.

Since I went full-tilt, just under 500 hp, chromed-out 455 motor transplant, anything short of headers would be silly. So I went all out for powder coated (inside AND out) Dougs headers that I find fit really well, look great, and the dual ceramic coating really holds down exhaust temps. But they are also pricy.