It didn't occur to me to do it any other way tbh, since I had an OE harness to use, and there's no reverse light signal up in the roof. The headlining was already down from doing the dents so actually it was pretty easy.
The headlining is held in above the rear doors with some extremely fragile clips which appear to be made from some sort of resin. Its almost impossible to get them out without them either shattering, or breaking off the headlining. So of course I 3D printed some new ones.
Hot-glued on to the headlining
Fitting a headlining single-handed is not the easiest of tasks so I contrived an arrangement to hold the front of it up in the air while I put the rear up
The printed clips worked perfectly
Headlining in place
I had a dig through my oddly plentiful collection of platinum bits and picked out the best bits, and then cleaned them all up which is considerably easier on the bench than in the car!
New single-use pillar trim clips
Driver's side A-pillar back in place. I replaced the door seal too since that was quite scruffy.
