Three high quality sleeps later, the upstairs bed platform has been declared a success, and it's onward ho to build out the front storage area. After installing the "floor" and covering it with the same indoor/outdoor carpeting as the bed platform (I don't want to hear stuff rattling around up there while I'm driving), I made a cardboard template for the bulkhead...
...and then cut the bare 1/2" plywood face. Then in keeping with priorities, I promptly put the golf clubs up there to make sure the opening was big enough. Check.
If you're wondering how one secures pretty much anything to the inside of a fiberglass hightop, here's the solution I'm going with:
Each of those wood blocks has been epoxied to the bare fiberglass wall, which I reached by cutting out an appropriately sized section of fabric liner and insulation. I then used pocket screws to mount the bulkhead to each block. Toss in a few L-brackets along the inside bottom of the bulkhead, and everything feels rock solid.
Better still, the bulkhead ended up perfectly covering that ugly seam in the fabric liner – exactly as I had planned it way back when I was installing the liner. Love it when a plan comes together like that.
Above is where things stood when rain cut work short today. I still have to trim the outer edge of the bulkhead, and then put a big honking door on this thing, but since I'll probably have to make a few more cabinet doors, I'll probably wait and do them all at once.