Chris if you want you can remove the metal bolt holders from the PU then grind off the the remaining threaded part then get a new bolt and tack weld it to the the strip, refit strip with new rivets, its a bit of work but then your will have a properly functioning assembly.
When the PU is installed spray some white grease on the exposed areas of the studs, this helps for fututre removal.
To fix the light housings, I tried to JB weld the studs back into the housings , they quickly snapped off once the nuts were screwed down.....So....
I removed the housing and got 4 sheet metal screws and drilled precision holes into the center of each stud mount ( the drill has to slightly smaller than the screw so the screw wont crack the plastic) Then with the new mounting I installed the housings with the lens fitted, best to keep the lens to the inner area and have a gap at the turn signal area, since the lens pulls straight out .
This took a bit of doing on a big blanket, anyway the housings are now tight and the screws that hold them didnt create any more damage .