Robby,
If your 73 2.0 is still all stock EFI, then you're best to stick with the original part no. ECU (brain).
If one of the above used ones aren't operable - or if you'd rather get a rebuilt/reman one with a warranty, then you can send it off via Pelican to get it rebuilt by FIC/BRET (actually core exchange). I had one done by the same BRET company when they were still in SoCal & it worked fine for 5+ years & another 50k miles, & probably still works 30 years later, but I haven't overhauled/refurb'ed & fired up the engine yet!
http://www.pelicanparts.com/cgi-bin/smart/...29%2C%20Each%20I have no idea what the turnaround time is, but call Pelican & they can tell you. You could also get one of the used ones from a member, then send yours in for a rebuilt by BRET as a back-up.
Good Luck!
Tom
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