I "popped" one of mine off to clean it, it was room temp. Be easy, poly is brittle and these things are ~$3K now (I think). Each.
new headlamp assemblies are now about $1,300.
^^^ I have "stuff" on the inside too. And some disintegrating top coat. BTW, new headlamp assemblies are now about $1,300.
They were higher and now they are lower. Maybe they got a Chinese supplier. $1,300 +/- everywhere. Here for example.
So you've made it as far as Lower Alabama!
Read the fine print. Old and new part numbers and they do specify driver and passenger. Click the links they provide.
Ford keeps them when they are replaced.