If you want a header that fits very nice and can change all your plugs in less than 10 mins, check out hooker super comps #5204 There are 1 3/4 and fit great around a manual steering box, also you dont have the #5,7 plug wire problem.
those #5402 hookers are easy to instal and they fit pretty good but they will not fit a 73 or newer A-Body because of the redesign of the front suspension that came in 73 :(
i have a set of those in my garage rusted to hell but still a nice set of headers, have tried flowtech and hooker #5116 and the big diference whas that the hookers where eaiser to install due to a slipjoint on the #1 cylinder tube, both made it realy timekiling to change sparkplugs.. i know have TTI and they fit great and if i had not bought them i would already have bought 3 more sets of headers since i refuse to drive around with seriusly flattend primarytubes