I have the exact same problem with my doors. I’m on the fence about taking them apart and laminating the outer fibreglass skin onto new plywood backing or replacing with new.
I’d like to reuse the fibreglass skin so it colour matches and the decals match but I’m unsure if I can get the outer metal trim off without bending or damaging it or if I can I get the old rotted panel off the back of it without damage as well.
I think new would be easier but much more expensive. The new white doors will be bright compared to the rest of the tt and I will have to somehow replace the decals or remove the remainder on the tt which will leave visible discolouration.
'17 Ram 2500 Crewcab Laramie CTD
'13 Keystone Bullet Premier 310BHPR
Hitched by Hensley