Thanks everyone! Great stuff in here.
It's not the antenna hole, not sure what it's for but I found some 3/4" body plugs for cheap so once it's painted, they'll get plugged.
I would love to sand blast it but I don't want to clean up the mess and I don't have the resources to take it somewhere and have someone else do it. I did the engine bay on my old Falcon; made a nice plastic "tent" in the garage to contain the mess yet I am still finding dust/media in places in my garage not to mention the dust it left inside the interior.
Rust is not bad at all. All light surface rust, no bubbling, no flaking.
FleetFox, You are the second person to recommend the permatex stuff so I'll probably pick some up.
After the engine was removed, I push the carcass out and pressure washed it with some Castrol super clean on it. Most of the grease and grime was removed but there is still a little. I will still plan to clean it off before addressing the paint.
The picture makes the paint look better than it is. Last night I removed the heater and blower boxes. The paint is coming off in flakes, almost like there was a fire inside the cabin and it burned it off. Weird.
Any who, my plan for this week:
A) Scrub the area down with some Castrol Super clean to make sure all the grime is gone
B) Hit the whole area, quickly, with my 4" knotted wire wheel to remove the flaky paint and heavy grime
D) DA Sander with 150'ish grit to remove most of the rest of the paint that has been compromised and the rust
C) Spray the whole firewall with the Permatex rust treatement, then let it cure for 24-48
D) Cover the whole firewall with a coat of sandable primer, sand, and base coat it Saxon Yellow.