It's thinner at some areas because of the moulding process. The start with a .060 sheet and it stretches over the mould and becomes thinner somewhere. The roof should be thick.
Yea it is for sure and whole cab area really, the nose is to just at the bottom on the sides is thin and found the hard way since its been pretty cold here so I would keep the body somwhat warm with a heat gun and I got to close one time and now theirs a little bit of a warped spot lol. Oh well its a body I can live with it.