Found an unexpected way to remove a 240k vinyl roof a few years back. I was a passenger in a tired old auto 240k that was held mostly flat-out from glen osmond to murray bridge. A little after mount barker, we heard a weird bang/thump from the roof, we slowed down but couldn't figure out what the problem was, so back up to speed, and when we got to murray bridge there was very little left of the vinyl
Max speed for that run was around 190 down hill, 170-180 on the flat and anywhere down to 120 up hills.
That 240k was the best $55 my mate ever spent (once we fixed the wiring it never missed a beat), did two decent long distance interstate runs and copped a hell of a lot of other abuse, and the only thing it ever needed was ridiculous amounts of oil Pity it's long gone...
Jonno.