After much experimentation, I have done the final install and config on my FS.
I was using the 2S Zippy battery, but when I got my EZRun I discovered it was way undergeared. As an experiment, I put the fan on the BEC and tried one of my 450 heli lipos. I'm getting top speeds in excess of 40 mph now and everything stays cool. So the new zippy 4000 battery is going up for sale and I'm getting more 3S lipos. It's nice to have everything running on one kind of battery.
When I moved the ESC fan over to the internal BEC, the BEC was overloaded. The Spektrum RX started rebooting at 40 mph. I got an external BEC and the internal BEC only runs the ESC fan now. Everything works fine this way.
I'm going to the beach and run this thing up and down the sandbars for a while. I've got three lipos and two chargers for this car now. Nonstop LOL