The best, easiest, and safest way is to use a heat gun. You can pick one up at home depot for like $20. Use a flat head to pry them apart. Some may suggest using the oven, but I think that isn't too safe for the headlights. The plastic could melt or start to haze up a bit. Oven is the esasiest if you know you can do it without accidentally overdoing it, but with a heatgun, there really is no way to mess up unless you purposely do it by leaving it in one spot for a long time. Then ones you pry it apart, its a piece of cake from there. Just remember not to touch the reflective pieces. Oh and I also found it easiest when I you start working from the inside corner....where the high beam is.....going out......to the signal. Start going from the top inside to out or vice versa and then once you reach the outside, the go on the other side and do the same. Get what I mean?