If not too late, I like my Sanderson DD9 short headers for the early A-body cars.
Provides room for maintenance, can install the oil filter directly to the block and plenty of clearance for your starter.
I previously had the TTI stepped headers and while a very nice product, they provide no room for the items mentioned above. Doug’s might be better.
For a street car I did not feel or hear a difference from the switch. Probably would on a dyno or drag strip.
Picture shows the spaghetti mess of the tti’s
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