Randy,
I have in the past succsefully vacu formed canopies, I did not however use the tooling, female, male process. I formed my canopy buck out of hard balsa, glassed it, sanded it, primed it with catalyzed primer,, then used it just like that. My box was about 18 x 18 and about 6 inches deep just made out of pine and a sheet of 3/8 ply for the top. Then I cut an opening in the side to fit the crevice tool into , wrapped the crevice tool with saran wrap and mixed up a slurry of microballoons and epoxy, slathered that around the crevice tool to form a nice guutentight fit. Then I put my canopy mold on a pedastal of 1/2 inch scrap leaving a small reveal around the base of the canopy to draw against. However in hindsight, I figured it would have been better to make it a continuation of the canopy shape with a slight flare at the bottom maybe,,
I then drilled a series of holes around the mold, seems like it was 1/8, or 3/32 inch holes about every 1/4 inch. Heat the plastic up to the correct temp, with everything sitting there waiting, I had better luck with the vacuum running when I put the plastic down. The mold pulls the heat out of the plastic pretty fast. Oh and make sure you leave a LOT of scrap area around your plastic so it can stretch. Hmm oh yeah, I built a frame out of 1x1 to staple the plastic to.