That is EXACTLY what I had finally figured out how 'your confused'(haha how ironic of a name) was saying.
The one thing that gets me is that when the lexan stretches it's gonna get thinner than the 1/8" it already is. I think I'll try a thicker piece next, maybe 3/16" or even 1/4". The 1/4" would probably thin out to about 1/8" after it stretches.
I think before I open the bag of plaster I'll try out the strech-over-the-headlight idea first. That way if it works(probably will) I can get my $15 back