IMO on a digger there only one way to mount in, like Glenn has, tilted to avoid airlocks rather than airflow. On an altered you can use a small one upright and have a model t etc grill shell over it.
If you're running brackets or gas, having the radiator and fan is the best thing you can do. On my BBC altered it allowed me to drive the car back to the pits and be cooled down ready to run the next round before most of the dry block guys had even towed back. It also takes all the panic out of any startline holdups, I've seen guys raving at the starter for holding them after firing, I sit and flick the fan on (always had the pump circulating). Mentioned it before but the best cooling aid I had (running mid 8's on pump gas) was locking out the timing. Running timing all in dropped my temps considerably and extended the window which I could run the car for.
