Dave,
I used a bi-metal toothed saw. A cordless drill is what I have found to work best with the hole saws. Just be carefull when the saw goes through!
You should have better stiffness with the t-nuts riveted circumfrentially. I went with longitudinally to obtain a more flus fit with the option of adding two rivets per t-nut, although that might add a half an ounce to the stove weight
I just started on my latest project: Light hiker boots with removable liners so they can be dried each night.
