You guys got me scared of tti headers!

I tried a set of TTI shorties on the 340 in my Duster. I switched back to my Doug's. The shorties have clearance problems too, just different ones. You can see my write up here My "new" '74 Duster- or why I need a project like a hole in the head

Really I think you just have to be prepared to add some dimples to whatever set of headers you buy, TTI's or Doug's. These cars tolerances are different enough that some will work better with TTI's, others will work better with Doug's, and you won't know until you try to install one or the other. Or both. Personally, I like the Doug's better. But on my car with a spool mount K and 1.12" torsion bars I did have to add some dimples to clear the torsion bars. After seeing how the TTI shorties fit though, I wouldn't doubt at all that I would have needed to do the same with the TTI long tubes.