The way it was described to me (and I only chime in because I'm a newby myself - and maybe as a noob I can speak noob language)... ;-) but...
... it doesn't matter how cold the cold end of the cage gets. The important part is to make sure that the snake can self regulate between the hot and the cold.
The only danger to the snake, and why thermostats are used is to keep the hot end hot - without the risk of overheating the snake. Snakes can cook themselves if the hot end gets too hot.
So... I've been told - setup the hot end to be the upper temperature, and let the rest of the cage work itself out. (This is for terrestrial snakes - ones in tree's I have no idea about).
Thus - putting the termostat on the hot end allows the heating element to remain active until it gets to a set temperature, and then stops it from going into danger zone. If the snake needs to cool down - they go to the cool end. If they get cold, they go to the hot end.
In the end it sounds like Selly's silicon may be best to glue things down. It's easy enough to peel off if needed. But as for my thermostat if you put it under the paper substrate - it can probably just sit there without been locked down. I second
@Herptology do not use tape! I've seen horrible things with snakes and tape.
As for pet stores - they're like any other retail store. They all have opinions - but most are there because it's a job. People here are here because they're enthusiastic. Choose for yourself who is more interested in learning what's best for their snakes and who to listen to. ;-)
