if you can find one of those mylar bags that hard drives are shipped in, the tough
metallic mylar with air bubble sandwich. not the easy to pop air bubbles, this stuff
is tough

anyway cut one of those into an insole and slap it down on the lowest layer of show bed

second to this, cut an ordinary metallic mylar footbed non-air bubble. go to a computer
store or shop if you can't find mylar, should be able to find lots in the trash



specialized defrosters standard footbed it not as well desgned as lake, for instance. lakes work great



also,

if you have room in the toebox (and you should)_ tape a handwarmer on top of
your toes on top of your sock. that will keep your whole foot a lot warmer.