Just thought I'd pop an update in here as to how my screen reshaping went.
I bought some 5mm perspex from a plastic wholesaler and cut it to shape. I heated it for 15 minutes at 180 degrees C. The perspex is very workable at that temperature and forms readily.
I made myself a jig in the same shape as the Tiger Tall Screen and clamped the hot perspex into it to shape it:
I then cut the perspex to a more attactive shape and mounted it:
As this was just a protoype it is very rough around the edges, and the perspex is a bit rippled. It is very hard to work with and to keep looking neat and tidy, but with more practice I think it's possible.
The screen has made a massive improvement to the buffeting problem I had, so I'm pleased, even if it looks a bit "ugly".
