Based on what I've seen you can run just about any AFB or TQ you want (depending on which style your engine came with originally).......... Not that I agree with that, personally I feel that if the carb has an obvious outward difference in appearance you should be limited to using that style, say a 71 TQ vs a 72, the 71 canted mixture screws are a dead give away. Now, if you could somehow make a 72 TQ APPEAR to be a 71, I'm ok with that.