Hey Ed,
I thought of that thinking it was one piece, but the inner liner seems thin and there is foam between. So thru bolting is just going to crush the thin inner liner and foam.
I think it is fine in there, so i probably just run a bead of 4200 or 5200 along the top seam and call it good enough.
I will ask the wife is she can grab/shake the hardtop and see what happens .....
