Here is some info for thought:

From left to right: Original from my low mileage ’70 Hemi Challenger, MOOG replacement, Original (I think) from my ‘66 Hemi Satellite.

As you can see, the MOOG is not the same..... I needed to replace the pitman arm on the Satellite and wanted “the best” so I searched and found a MOOG piece. I installed it and took it for a quick spin. I promptly ran the pitmen arm and Zerk fitting into the ceramic coated header primary tube and did a fair amount of damage to the tube.

With all of that being said, these headers were 2 1/4” primary tube....

I ended up giving the MOOG to a friend who has a stock ‘66 Belvedere with exhaust manifolds. Clears everything fine.

Stan