Hello

I'm new here and I'm from France.
So sorry for my english that should be a bit "old" (learned during my studies).
I recently bought a 92 firebird 3,1L V6.
My question is about the rear hatch release.
I read a lot here about but couldn't find the answer I need...
On my firebird, when I bought it, I didn't have the hatch release with the button on dash pad.
So I bought one with 3 switches (defrost, fog and hatch release).
The wire on the car seems to be there (behind dash pad) and I plugged the switches.
But for the rear hatch release, it dosen't work.
My pulldown is the tight plastic one, so is different than years before. On that kind of pulldown, you can't add a solenoid...
Do I need only a relay ? Is there two kind of "plastic" pulldown ? What do I have to add ? And if someone have the parts I need, let me know the cost....

Thanks for people who answer me...
Arnaud, south of France