What parts from lower case are required for MacBook to work?

I am handy with wood, but not so much with logic boards. My MacBook works fine but the plastic exterior is crappy and I thought I'd replace it with wood--after all, I am going to use it in my wood shop.

Now that it is completely disassembled I notice that the portion of the lowercase that sits under the logic board is metal, insulated in some places, but exposed in others--especially where the screws hold the board in. Does this metal serve a purpose? That is, does it conduct electricity? How about the metal brackets around the various ports (firewire, usb, headphones)?

If I screw everything down onto a pice of wood without this metal, will it work?