Once I had enough foam removed so the top cowl would fit, I made some alunimum blanks to fit the fron of the baffles. I installed the cowls and traced the intake shape onto these blanks. I marked a line 3/16" outside that traced line and trimmed the blanks to fit. I glued and screwed these intake templates to the foam.
I cut and shaped the foam to match the contour of the intakes and the baffles. I used course sandpaper and a hacksaw blade for a lot of the work. The best tool I found for working the foam was my file card. It is just the right level of abrasive to make fast work of material removal without tearing the surface.
Once I was happy wih the contour I used some wood filler to seal the surface and fill some gaps. Once the filler was dry I sanded it smooth. I covered the whole thing with plastic packing tape to act as a mold release. The packing tape also bridges small gaps and smooths the surface.
