I don't know why you couldn't use sheet metal, though I don't know how the seal would work since the sheet metal is a different thickness than the glass. BTW, I don't think that a replacement glass is doomed to crack - many people have ovens much older than that without cracks - and self clean cycle gets a lot hotter than when you make pizza.

This post was edited by Barryv on Sat, Aug 31, 13 at 21:05