you can always go the hedman tight tube route , cheap , easy to install , no problems getting the starter or plugs , and make good power . I have them on my 70 340 and car runs faster than with the old hooker headers . Hardest part wart routing form collectors to exhaust . Hve yet to bottom out and mine are routed ubder the steering . There are oics in other threads , also txstang has them routed above steering so really good clearance .
Of course mine is a mild build 413 hp 398 torque , so headers help over manifolds .