Hi Ben
In order to remove the door handles it is necessary to twist them through 90* when you have pulled them back as far as you can. This is because there is a ‘diamond’ shaped retainer just inside – in effect the square of the handle turned through 90*. Even then they can still be a bit fiddly to remove so plenty of WD40 or hatever you use.
I have never come across brackets specifically for fibreglass wings on any of the parts supplier websites so you may have to make your own. However, no doubt there will those much more knowledgeable than I who might help you.
Headlamp pods are mild steel as far as I know.
Kind regards
Paul