Unfortunately drews, your 1976 49 State version Spider was indeed originally equipped with an AIR (Air Injection Reactor) pump. It's purpose is to pump air (O2) into the exhaust manifold to facilitate the burning of unburned hydrocarbons left over from the normal combustion process. If you PM me your email address, I'll send you the 1976 MY Alfa issued Engine Management manual for your Spider.
Most of the airpumps mysteriously fell off when the warranty expired so there should be some around.
Pretty good memory there, AF!
