The frp is no problem to work with, jimun, I'm just using frp adhesive. I'll be putting more screws in the trim to double secure it, as I don't know what will happen when the frp expands in the sunlight.
The only problem I had was coming up with ways to clamp it or weight it when waiting for the adhesive to dry.
It's also more of a weight penalty than I anticipated. If I had used aluminum and contact cement it'd probably be at least 40 lbs lighter.