[KobaltBlau]

RC engineering has a good reputation with injectors; they use the lucas type (not manufactured by lucas, just the original design) which is a plate type valve as opposed to the slower reacting pintle type, main difference here is the pintle type might not keep up with 8000rpm. buying new from them will not be cheap though, you could probably get away with junkyard injectors just fine.

as far as mounting angle and injector spread, you might try to find more information on the factory MFI with injectors mounted high above the butterflies. I don't know what injector spread they used (probably regular MFI, what's that?), but I agree that the straightest possible shot from up that high is a good idea. modern fuel injection sometimes tries to spray the back fo the intake valve head but your injector is much higher so that doesn't apply. I also agree that the narrower spray would probably be better for your application.

My concern is that your 73 is still street driven part of the time (isn't it?). I have heard people recommend against butterflies below the injectors for a street driven car for driveability and fire concerns. Whether these are valid I can't say as I haven't built such a system.

Would you be allowed to run Webers or PMOs in your class, on the same engine? (not suggesting it, just trying to clarify rules)