It even has two kinds of hoses (one hose and one tee) for the aux air valve. My 78 didn't have the tee fitting, and I've seen many others with the tee

my early 74 260z had one on it and I took it off. much better as mine had a habbit of holding the throttle open

I think the B.C.D.D. is just hooked into a switch inside the speedo, so disconnecting it & removing it shouldn't affect the way the engine runs- but you have to plug the hole it was from. More wiring diagram research needed. I think you'd probably just get a puff of black out the tailpipe when you let off the gas pedal.