I think the following is the process. Someone will correct me if I'm out of order.

First, check the frame for square and have it straightened if appropriate.

Then, make any modifications to the frame you plan on making( c-motch, mount plates, etc..)

Then:

1- Strip to bare metal (sandblast, wire brush, sand)
2- Powder coat OR:

2- Etching primer
3- wipe down
4- primer
5- scuff sand (some say its optional)
6- wax & grease remover
7- tack rag
8- paint (1+coats, scuff/sand between coats)

'51 Chevy 1/2 ton w/'62 261, HEI, offy, fentons, dual carter/webbers, t-5 & 12 bolt posi