yep, still air box is the correct term I think. It was a cardboard box with two armholes cut, and saran wrap stretched over the top.

Put all my equipment inside, stuck my arms in to more or less plug the holes, then sprayed a bunch of rubbing alcohol all over the inside, then got to work. The ergonomics were horrible, my back got tired, and I'm pretty sure my arms didn't plug the holes very well and I assume they effectively were pumping air through the system by the end of it as I got sloppier.

Definitely will do something better on any future attempts, haha

The easiest technique is getting a big plastic tub (>90 qts) from Walmart or Target, heating up a coffee can on the stove, and burning the arm holes in the side.