Making your own canopy

I know this has been beat to death over the years, but, I am ready to
proceed with canopy fabrication. I am fortunate enough to have a
canopy tool (female mold) but am unsure how to proceed. Use the
female to make a male plug and try stretch forming over the plug? If I
use this method, how do I compensate for the thickness of the plexi
when making the plug? Or I could use the female and attempt to vaccum
it down?
I have an oven started, a huge plywood shipping crate about 6'x4'x4'.
My plan is to heat the plexi and plug together in the crate and upon
reaching proper temp, slide it out and stretch it down.
I have already sent photos of the tool to a canopy house and they
estimate $3k to make one. I figure I can burn up a lot of plexi for
that.
Words of wisdom appreciated.
Thanks,
Clark