Been awhile since I messed with them, but was pretty simple as I recall. Trucks were not CCC *unless* new, they were originally destined for CA.
All sorts of weirdness AFTER 1986, but generally trucks were not CCC (again except if CA destined originally), all US cars were CCC 1981+.
And to clear up any possible confusion, all 305's '81+ had ESC/EST (electronic spark control or electronic spark timing) due to the higher compression, but that was a distributor only deal essentially.
CCC had two electrical plugs (three if you count the choke): Mixture control solenoid (passenger side, top, front of carb) and Throttle position sensor (drivers side, front of carb). GM had a good variety of non-CCC carbs with electrical connections where the MCS was on CCC, but that was something else.