Gus, I blasted my sub frame a 2 years ago after reworking the mounts and such. The surface was etched nicely from the media I used, and after it was cleaned with a solvent based cleaner, I used a product called Chassis Saver. The instructions were very specific in stating the product went on to BARE metal. It has a satin finish, and I brushed it on. It could have been applied by spray I suppose or reduced for spray.
