Replacing tires
The oven trick works like a charm but be forewarned, your kitchen will smell like roasted tires for a bit.
Preheat the oven to 450. Put the tires on a baking sheet and put them in the oven and turn the oven OFF. Let them sit in there while the oven cools (I left mine about 40 mins). The heat crystalizes the glue and it'll just crackle and break when you push on the tires.
Sand the rims a bit (if needed) and you're ready to go. It won't melt anything, as long as you turn the oven off (even tho the smell might scare you--it did me). Works like a charm!
pb