86 Chevy underhood wiring - identifying connectors?

[Nick_R_23]

I have a few connectors under the hood I'd like to get an ID on if anyone recognizes them.

#1. Rear center against the firewall. I *think* this may go to the A/C compressor as the wires head from the A/C box.



#2. Drivers side, this one plugs into the transmission vacuum switch, but I'm unsure where the orange connector goes



#3. I believe this is choke (light blue) and head temp sensor (green).



#4. Unsure what this one is...sensors on the carb? Will it hurt anything to keep these unplugged?



#5. I believe these are oil pressure sensor and oil pressure sender. Would this truck have had both?





Thanks in advance for any help!