So, today is the dreaded day of the canopy. I've never Vacuformed before or made clear canopies before. so here we go. I'll be making the plaster cast for the canopy later today, but here is the basic pdf file template for my box. It is out of foam board, and for the side with holes, make sure to cover it with electrical tape and duck tape for insulation from the hot plastic. The size is 6.5x6.5, effective area: 6x6. To print it out, you can use Adobe Acrobat and in the print settings find the tile or poster setting. Once you tape it together, you'll get a full size template that you can tape together. Also, i didn't make a hole for the vacuum cleaner, only a big center mark, because your vacuum pipe might be different from mine. Here goes nothing!
P.S. I was inspired by YOAV's vacuforming guide, so here's that:
Vacuum form