my After market has same dash evap, blower there, I installed mine. (all)
mine has high/low switch right fender on top of receiver driver unit.,(see photo mine) yours is different model A/C)
all cars made , have extra connectors. for things not opted day one new.
no maker of car makes hundreds of harness versions for all permutations of options, (huge) (imagine the cost of that, making ,storing it)?
so all have connectors doing zero. on all cars made, never once did I ever see an exception. unless you ordered the car with all options. nah...
just safe them off. (tied back) as they did day one new.?
some AC back then was the dealer option installed. so one more variance there.
also the free service manuals cover all wiring, every inch and the colors of the wires. making connectors loose easy to ID. (unless hacked or some aftermarket things stuffed in) after 36 years, stuff happens.
seems yours is 2.5L TBI injected. TB there has the funky idle IAC mess. so. is.
see the A/C compressor, see the 2 huge hoses. the condenser, up front goes to the receiver dryer, and the switch.
mine is very powerful A/C even on 110f day
Good luck making any 36 year old car run good. (lots of work it is)