If it were mine, I would put the factory T-handle on and get it working.
After that, you can switch to the other handle.
The shift mechanism isn't complicated, if you take a look and none of the channels are excessively worn, it will work.
All of the metal frames for the dash pads have the cut outs in the metal for the AC vents.
I'd think you could carefully cut away the foam and use stock vents.
That connector to body ground is marginal.
I installed an LED Bulb and it wouldn't work.
I ended up soldering a wire to the socket ground and running it to the mounting bolt for the shifter. Works great now.
In the future I'd replace the socket with something that has a dedicated ground wire.
Yes, link shows later screens for reference.
You can find cheaper elsewhere
https://www.classicindustries.com/product/1973/dodge/challenger/parts/ME1562.html?gclsrc=aw.ds&gad_source=1&gad_campaignid=10557155918&gclid=EAIaIQobChMIxNjpkrf5jwMVAZ1aBR3dEx6bEAQYAiABEgJ5BfD_BwE
I had the opposite...