FWIW, places like Jet Performance use the late 70's (170 prefix) qjet bodies for their stage 2 units. They drill out and tap the air horn so you can adjust the APT externally. Other than that, they enlarge the mixture screw orifices a bit, plug the idle-air bypass, and they replace the primary jets, rods, and secondary rods & hangers as needed. Mine ran decent out of the box on my old engine (my new 383 required enriching the idle to primary transition circuit, opening up the idle-air bypass again, and larger primary jets/rods).
These later qjets use a different primary rod length than the earlier qjets (and the Edelbrock version, too)... Sometimes parts can be tricky to find.
Cliff Ruggles book is a great resource...
These later qjets use a different primary rod length than the earlier qjets (and the Edelbrock version, too)... Sometimes parts can be tricky to find.
Cliff Ruggles book is a great resource...