Wow now thats a real death trap. Unbolt and remove the steel bug body which is weak as **** to begin with from the beetle floorpan / frame making it even weaker, and bolt that to a fiberglass dune buggy tub.
A buddy of mine has a sand rail buggy. Only thing it uses thats VEE Dub is the front suspension, and rear transaxle. Everything else is welded tube steel. Its got an adaptor on it with a corvair flat 6 in it. I'd take my chances in a sand rail before i hop into a fiberglass tub body dune buggy.