[elhigh]

I've seen this a few times. Even Mother Earth News showed an article on it, back in the day - a homebrew rig that was a pot inside a kettle, and exhaust routed through the space between. That stuck out behind the truck, so I imagine it looked kinda weird. Convenient though - no lifting the hood.

I've done it a couple of times with heavy-duty aluminum foil. First you make up your meal and package that inside a tightly sealed pocket of foil - crimp the edges to keep any crud out. Then make a tent to go over that, and park the whole shebang in the V between cylinder banks. The tent keeps excess draft away and lets things get nice and toasty. You might be able to do without the tent. If you've got a turbo, there's a serious heat source right there.

Thinking about it, it may be more of a waste energy-wise to do up a meal like that and then throw all that aluminum foil away. But it does a good job of using heat that might otherwise go to waste, and you can save a few bucks eating on the road, instead of -um- roadside. Anyway.