Re: SY1 intake
Yes, That is a Performer RPM, but not an air gap. I have never seen a SY1 intake, so I can't say if the wall thickness of the intake is enough material to mill. I would guess, No. The only reason I can think of why to use that intake is for nostalgia and you would want a small bodied distributor to be period correct any way. You can add a pertronix kit or similar to the small body to get electronic ignition.
69 Camaro -originally a LM1 car. 327, Edelbrock E-streets, hooker, DUI performance distributors, ultradyne cam, stewart, TRW etc. Vintage Air, AGR steering, Corbeau GTSII seats, 700R4 transmission, 12-bolt w/Eaton 4.11:1