Thats not bad, but you're gonna wanna get 10mils for the rear as well to even it out. See if they'll give you a better deal for 4 sets and I'll take 2 pairs
Warm paint = flexible paint, heat gun them as you go, not just before you do it. I don't know if it's needed, but I'd throw on some blue painters tape just for the extra protection but it's probably not needed. It's really forgiving so won't remove any.
Found you a video, just make sure you do everything he says