Atwood Everest 12,000 btu Heater (8012-II)

Well fellow campers, I have used my Wave 3 quite a bit, but a the lower temps it just doesn't have the BTU's to keep the TC warm, and since we live in Alaska, the lower temps I am referring to are freezing and below.
So I just got a great deal on a brand new Atwood Everest 12,000 BTU heater that I will be installing in my 1966 Avion C-10. It is pretty compact, and yet does well on the BTU's. My question is for those who have used, maintained or installed these little gems, do you have any advice?
Thanks!
Garry