https://www.scionlife.com/forums/viewtopic.php?t=32050. this says that to get the headlights apart you need to put it in the oven for 5-10 mins at 250 degrees, but I don't want to risk it and i'd have to take off my eyelids for the 4th time. So I was wondering if i can just use a hair dryer or a heat gun.

 

I have had some experience with dismantling headlights so using a hair dryer is a no-go. The hair dryer doesn't produce enough heat to soften the silicon sealant in the lights. The only alternatives is to use an oven or as you suggested a heat gun. With the heat gun you have to keep the heat moving. Even on a low setting heat guns can and will melt plastic if left in one spot for too long.

Ovens work good since they can soften all of the silicon at once and you get excellent heat control. IF you do want to try the oven method, I suggest doing it in an electric oven only. Gas ovens don't fair to well when it comes to this kind of task as you can have difficulty controling heat dispersion. Also use the lowest temp for all heating purposes. If you find you need more heat it's always better to add more heat.