I haven't had much time to work on the Beetle, but I did find an oval/ragtop section near by over the summer:
I was a little worried about the fit, but the center roof section on my chop, is actually a "new" piece of metal, formed pretty close to the right bend, but has a good amount of body filler to make it the right shape, so I didn't feel too bad.
Original Chop:
Trimmed the roof:
Marked the section
and test fit the ragtop:
Haven't had time to finish it, but hope to get back on it soon. Need to weld the rear oval window section in as well, so it should be interesting!