Shrinkable plastic for a form?

[firstgenaddict]

I've used a poly tray about the size of the intake heat the intake and tray inverted over the intake in the oven on lowest heat setting the heavier sides will pull the edges over the intake edge... I tried to do it with intake and valve covers and didn't have a large enough oven.

You can make a vacuum table using pegboard and a few shop vacs build a box with the pegboard as one side drill holes for the vacuum ports and use a piece of plastic the size of the table heat in the oven with the intake on the vacuum table pull sheet out drop over and pull the vacuum... viola'
\