I know you seem to working on a Small Block but I side with Fred, I too went thru the Hooker "Header Roulette" for my Big Block install into my 69 SSRS.
I talked to Hooker and Summit, Hooker said they are the Proper Listing for my car, another Team Camaro member has the same 69, Engine is a BB and also has Power Steering and does not have any Fitment Issues.
Summit said Hookers Tooling and Manufacturing tolerances are not as good from Header to Header.
I put a set of Doug's D320's, yes, not for a Small Block but Summit took back the Hookers, no questions asked.
2 things I would look for is if too close, could be a Heat issue and sound problem if you only have the Carpet, hate to heat up the Carpet and see it start to smoke.
And what does it look like from the Side, we all look at angles and Header/ Exhaust System Installs, a pitch up too much with the Primaries and Collectors, for what we pay for these Headers, they should look right too
I wanted to stay Loyal to the Hookers, had'em in HS but also needed something I did not have to work over with a Torch and Ball Peen Hammer.
Timmy from Trumbull, CT