Mark & I discussed this off-line, here is the short version of my response.
"I agree a nice fiberglass hardtop for the M100/M416 trailer has commercial potential. The one possible barrier is the high cost of crating and shipping items this size. Part of my envisioned model lineup for the fiberglass bolt-together trailers is a M100/M416 replacement tub and evaluating a hardtop for it is part of the plan. Once I get the initial Jeep tub kits stabilized and shipping, I'll do some market research to determine which model makes the most sense to pursue next. Best case on this would be late Summer '12."