You will need:
1 Large Ice Chest.
1 Lamp with a flexing arm.
Small amount of strong adhesive (I used some spare epoxy)
Magic Sculpt self-hardening epoxy clay or other filler material.
*A Dremel is HIGHLY recommended!*
Step 1: Remove the drain plug
I've checked on a few different coolers and they all seem to just unscrew, doing this can be as easy as jamming an oversize flat head screw driver in and twisting.
Step 2: Route the wires
If you don't have a dremel, you'll either need to do this the slow way... or if you have a soldering iron you can try desoldering the wires from the lamp, running them through the drain, and reattaching.
Step 3: Prepare the base
Determine where you want the base located inside the oven and make a mark around the base.
Take your Dremel or sand paper and scar the PE liner, and do the same on the bottom of the lamp base. Don't be afraid to get aggressive, the uglier it is the better the surface is for your epoxy.
Step 4: Mount lamp heater
Prepare your epoxy or other adhesive.
Apply adhesive to both surfaces.
Place lamp and let the adhesive set.
Step 5: Seal drain hole
Let your filler material set.