You'll be taking the screen out, presumably, to do ther re-painting. Once the screen is out and the bonnet is off, you need to move all the wiring and anything else which gets in the eway. Then rub down the fire damaged area until you have bright metal showing. Treat it with a rust convertor like 'Jenolite', then prime it with the primer you'll be using on the rest of the car and finally finish it with the top colour coats.