Decided the front defrost would be a good thing to keep. Found 3" bilge fan and duct, like what is used to cool vented disc brakes. Problem, adapt a 5"x 5 1/2" flat flange with a 4"x 2 1/2" hole ( pic #1) to a 3" duct. This is where I start having a bit of fun! I have moldable urethane! A little flat rubber strip, some tape and a little math, voila, a mold for the adapter tube! (pics 2-3, the inner sleeve is the only one I have pictured, sorry.) I made the 3" tube and then molded it into the flat rubber plate, sorry, no pics on this. The flat plate didn't properly adhere to the tube, so I made the urethane mix into a putty consistancy and built up a fillet around the tube. See it in the finished product, no i'tain't perty. (pic 4). Will use silicone to glu it to the plastic duct, should look something like this. (pic 5 and 6) Mount fan to pull warm air from behind the radiator. That was fun, back to the wiring, sigh.............