I also want to thank you for the info on the SnuggleSafePad. I looked it up and it's perfect!
I've been using the
Self-Warming Thermal Cat Cushion. I figure if the cat loved it why not try it on the dog?
Although Prince likes to take naps on the self-warming cushion (and hump it from time-to-time I guess because it makes a crinkle noise)

I'm going to get the SnuggleSafePad for the cold winter nights.