The sockets for the trunk and defroster switches will be accessible behind the switch locations (unless they'be been moved).
There's a relay for the defroster just above the brake pedal.
Check your fuse panel for proper power access.
If there never was a trunk release solenoid, you'll have to fish the wire through the decklid to the connector that should be near one of the hinges depending on the model year.
I have found the factory service manuals to be very helpful with the schematics, diagrams and sketches showing actual connections and locations.
https://www.fierostore.com/...%20%2084CD&d=281&p=1[This message has been edited by David Hambleton (edited 01-29-2019).]