To answer your question about Trim Adhesive:
3M replied quickly. 5200 does not stick to HPDE,
3M is wrong....5200 sticks very well to a Wave skin. We have made a number of remarkable repairs including gluing on two wooden replacement keels that you would be hard pressed to tell, and a transom that was partially ripped loose.
I would fear that it would be too aggressive to install the underseat port covers if you EVER wanted to get them loose again.