Just an update, front fender is still away and the little heater would not fit anywhere that would be useful. I have been looking into installing a vacuum gauge on the bike to aid in efficient acceleration and DWL. It took some asking around on the four cylinder specific forum, but I did find and order the part I needed, a 6mm hose barb.
Update update: I found a 1"x1" square heater pad, will check dimensions on little cibbie's oil pan again and see if I can fit that somewhere. The other heater I bought was 1"x5".