Ok, I finally got my interior some what as a finished look. I used white smooth finished FRP for the headliner, secured wood block spacers, used mahogany batons and trim. I used the wood blocks to space the FRP off of the hull and to screw the FRP too. I used some mahogany trim piece I picked up at my local lumber yard and are pretty standard wood trim.
Mahogany trim used
I used the the Mahogany for the trim on the FRP, same as for the batons, but had to router one side of the trim to have both sided with a radius for batons. I couldn't get it with both sides with a radius. You can use the wider popular wood trim with both sides with a radius, but you would have to stain the popular. You can use a popular instead of mahogany if you wanted.
First step to using the FRP is to secure wood blocks in locations to space the FRP off of the hull and to clear hardware. I used polyurethane to secure my blocks. I then measured and cut the FRP. I chose to run the batons length wise so I didn't have to bend my wood batons, but it might be better for the FRP to have them the other way. I had to deal with the FRP wrinkling do to my center hatch. I used a heat gun to remove most, but still have more work to do to get them smoothed out. I didn't insulate my headliner, but adding Styrofoam to the back of the FRP would be easy enough if desired.
So, I did have some panel rot and severe water fade. I thought about removing and installing new wood panel, but Teak panel is expensive, and would be time consuming to do the remove. I had sections of the wood panel that I had to repair. I chose to cut out the rotten sections, woody putty the removed sections, and paint the panel. I know you purest might hate the look, but it was the most economical and time saving option. The interior of the boat is much brighter and cleaner looking. My wife likes the new look better then the, "old dirty, dark, water stained, wood panel", I tend to agree.
Blocks installed like below
Before remodel
You can see the water stains and wood rot in the above picture.
FRP installed but panel not painted
Panel Painted
You can see I put trim against the hull to hold the edge of the FRP. I used a brad staple gun to secure the trim to the hull, becareful on the length and how deep you shoot the brads, don't need them damaging the outer layer of the hull. I used some wood clue and as few brads as possible. On the lower portion of the panel I used a thin 1/2 mahogany trim piece. I then used the 1 1/4 trim, same as the batons, and upper section, to cover the FRP at the inner self. I should have just not put FRP in the self portion. It would be easier to just paint the shelf section and had the 1/2 trim covering the panel edge. I mounted LED strips to the 1 1/4 self trim piece, which also hides the LED. In the last picture, you can see a LED dome light I added, the red and white, 4 brightness levels, touch on/off.
The actual project wasn't to bad, figuring out where all the blocks go and how thick of a block to use took the most time. You have to make patterns for the FRP from thin cardboard of similar. If you skip the FRP in the selves, v-birth, and 1/4 birth, takes 2 sheets of FRP I painted my v-birth, 1/4 birth, and head ceiling and panel, much easier and saved on FRP sheets. Once again, the painting the V-birth, and head, brighten up the drape dark area of the boat.
So, that was my solution and input to the headliner issue.