how hard is it
The light lid is metal right? Same procedure for that.
Check out Eastwood or local paint supplier for filler. Avoid Bondo, as it's not the best product out there.
Grab some grey and maroon scuff(Scotch-brite) pads. I use these for the hard to reach corners. i.e., recessed letters.
Pick up some wax and grease remover, nitrile gloves, blue paper towels to help keep your job clean. Get a couple different sizes of masking tape too to help protect areas you don't want scratched/painted.
Take your time.
Best of luck!

