Re: Keeping it cool
In my experience, an electric fan alone won't cut it. Since you have a V8, I'd almost guarantee it. At least at low speeds (trails). I'd add the pusher to the front and keep your engine driven fan. Also, make sure your shroud forces air to come through the radiator and there are no big openings where air has an easier path.
I have had the same problem with mine. The big block is happy lugging along the trail at 300RPM, but there is not enough coolant/air flow at that speed to cool it. If I keep the R's up a bit more when she gets warm, it's able to keep cool. I have considered going with an electric water pump and fan, but the pump for a big block is about $175 and there are more pressing items to spend money on at the moment. That setup would be nice since pump speed would be constant, regardless of engine speed, and you would have the option of cooling the engine when it isn't even running.
'84 K20 driver
'80 CJ-7 BBC, 1 ton
<font color=orange>'79 K10 mud racer</font color=orange> (for sale)