Hi Mike,
Thanks for the update. It sounds as if you have "tamed the tiger".
My latest cold weather mod is called "magic carpets". They are electrically heated (120 volts). I got three and they draw about 750 watts. The surface temperature hovers at about 33 to 37 C, and the floor under them gets to 47 C.
As a side benefit the unheated insulated basement gets warmed up too. The coldest spot on the floor now is about 10 C. Before I had the carpets, that spot was often below freezing, even with the living quarters at 22 C.