[Christ]

Also -

Once this thing is running (if it gets running at some point, satisfactorily), I will probably have to completely block the grille and remove the radiator, replacing it with a smaller core inserted into a forced air duct.

I say this because I'll have half an aluminum engine making heat, and the other half acting like a heat sink... it'll be hard enough to get it to warm up, so I don't imagine that I'll have any cooling issues.