neil,
Yes I've done this before on a few shells for RRCi. All you need to do is cover the design you've cut with the same tape and lift it off of the lexan (you could use a peice of glass if you've got one too rather than the lexan) but you do have to do this carefully. then when you put it on the shell rub it down and pull the backing tape off. when you pull the tape off, fold it right back on its self and it will come away easier.
Not sure where you could get some spare lexan from though.
When i get my site back up and running I'll put a tutorial on it for this sort of thing.
