This interests me.
We now have a (pretty much stock/original) Model A that I drive some. For some folks my mileage would be miniscule. For others it would be a LOT. From the time I bought it in August of '25 'til winter set in around the first of the year I put 1,4xx miles on it. I plan to put a lot more miles on it before I die. I'd love to do some cooking on the engine.
Last month we drove it to a car show 350 miles from home. I'd love to have had lunch along the way in a city park or something that was cooked on the engine.
That said, I have some experience doing this, just not on an in-line engine. My 1948 Ford panel truck has had a small block Chevy engine it since the early '90s. I've baked potatoes on the manifold. I've reheated food at car shows. That is, gotten an extra "plate" at supper one evening, put it in my cooler, and reheat it on the fairgrounds for lunch the next day. I've even reheated casino shrimp out on the Bonneville salt flats the next day. That's pretty easy on a V-8 engine where you can just lay stuff on the intake manifold. Just take the stuff out of the cooler, put it on the manifold, and drive around the fairgrounds for a while. Then have a hot meal.
I'll be watching this to see what I can learn about cooking on a Model A engine. I'm envisioning welding up a "hot plate/oven" that can be slipped down over the exhaust manifold by having some "legs" pointing down.
Any pix that you all can post here would be mightily appreciated.