['ol Pinion head]

Original '67 GTO 400 HO/RA manifolds had 3 bolt outlet for head pipes, so do the '67 repro's. 3 on the right manifold & 2 on the lh began with '68 GTO versions. Yours are def '67 repro's, as original '67's don't have that thick a port flange area or the oddly placed casting run number.

Examining originals or repro's, the outlet on a LH 67 GTO HO/RA manifold is positioned slightly different than '68-69 & '70 (only) RA3 manifolds. Both original & repro '67 LH manifolds positioned the outlet slightly further back in the chassis. A deal I examined first hand decades ago. RARE had supplied a pair of their Dport manifolds for a '70 T/A resto. As a result the curved rear upper casting of the "67" drivers side manifold they suppiled interfered with the positioning of the clutch rod arm on the car's early 2nd Gen Bird z-bar.

As far as brands/different aftermarket castings go, as far back as the early 90's I bought numerous pairs of repro manifolds for customers cars. Some from Paul D (RARE), & some were pairs of '68-69 GTO Dport RA manifolds (through PY). The latter was the only competitor to RARE at the time. Classic of OH was the brand. For ID, Classic's own castings had the GM part numbers cast into them, but a CM instead of GM, was an easy way to spot them.

For the last 10 or so years, seems at least one more entity (possibly Parts Place) became involved in casting up reproduction Pontiac RA manifolds. Hopefully someone can expand on identification of the recent offerings. Do know CCass had a version of RA manifolds going for a while through PYPES.