Someone has recommended the Golderod Dehumidifier for cockpit warm up. It is an 18 or 36 inch light strip that lays on the floor under the instrument panel and provides just enough warmth to the instruments from fogging up. It is supposed to take very little power and is safe to just lay on the floor. Boating supply sites have them for about 25 to 45 bucks depending on size. Has anyone had any experience with this product?
I used these in my sail boat, which has been replaced by another airfoil. In my experience they did not have enough output to keep a plane warm. They used to be used reduce the potential for mildew in an enclosed environment during damp and cold weather. I would check with someone like West Marine for more information; http://www.westmarine.com/ or call and ask for technical advice. US and Canada 1-800-BOATING (1-800-262-8464)
I have used a smaller Goldenrod for years in my gunsafe. It basically acts as a dehumidifer but puts out very little heat. I don’t know if it would do much in the cockpit.