I've got this same heater in my 2 car also. As for the fan, here's the solution I used:
$15 box fan on chains about 12" from ceiling, cord runs across and down to a handy box with a standard light dimmer switch. Fan switch is on "high", dimmer allows me to adjust breeze as needed. Works great summer or winter. Been in place about 12 years, fan's starting to whine a little so I might replace it soon.