Hello! I have used 1500w elec space heater under seat and two heavy tarps that cover entire tractor. on top of tank 2 foam slabs 4 inch thick and carpet over that. In past,if temp 10 or so or less degreesF tractor did not start except htr left on. Thats kicks up elec bill too much. I contacted Cub specialty parts dealer-MBH1153(KAT) their offering. I know there are a number of brands-zero start,Kat etc. I read where some overheat and melt plastic cover. Please post your experiences on this. I have read some say frost plug best. The parts dealers for Cub dont mention frost plug.Any comments on this issue for Cub owners appreciated. Thank you very much!