I see you live in Lancaster PA, hardly a heavy snow area. I am in Erie County in a major snowbelt with the winds and snow coming off Lake Erie and temps can dip into the -double digits on some days during the winter months. I built my cab about 15 to 18 years ago and it is Aluminum and Plexi-Glass with no insulation at all. I did put some foam on the roof to cut the noise though, and most days when I am blowing snow I take my hat and gloves off because I am too warm! The heat from the transmission keeps it warm enough to keep the glass fog free unless I blow directly into the wind and it blows back on the windshield. What I am getting at is I think that heater will be overkill! Just my opinion! The cab so far look excellent! Great job!! cant wait to see the finished product. Ken. W8N4-SNO!