Does any body know if the early convert has a strenthened floor pan similar to the later bug cabriolet. Tom

Yes it does. Under the Heater channels there are strengthening rails, The Back seat Rail, is actually welded to the body (a lot bigger than a hard top) On the opening of the doors you will notice there is semi circle sections on either end, and there are also a few more that are not that visible.

N!