Here I am.
Yes, I have a set of 1968-1972 Nova headers on my 454 and they fit like champs.
I have the SM465 manual transmission and they clear the Z-bar linkage with room.
Here is a photo of my dirty gifted to me set of headers from a buddys big block Nova.
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They went right in from below and have had many many miles put on them.
The dents in the tubes were from the previous owner having to adjust them for his fit.
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Looking under my truck this is what you will see of the exhaust....
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You can clearly see just how tight they tuck up in there.
The front crossmember is much higher than the lowest part of the entire header.
Placing my head on the ground of my stock height truck, you can see the collector hiding up in the chassis.
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