<<and that is typically far too hot. So if your t-stat shuts off and allows it to reach its maximum setting, it can be bad.>>

Boy is THAT an understatement!! The temp on the floor where the heat mat is was 138° when it settled!! I unplugged it right before I went to work. I'll have to see if I can find one of the dimmer switches! (Thanks for the link to the pic btw ... an IMMENSE help!) Of course, the cool side of the enclosure is 75. (During the day.) Very tricky ...

Any suggestions?

Peggy