87 Fifth Ave Rust Repair after Bonnet removal

As I continue the journey on this 87 Fifth Avenue, I got to the Landau vinyl roof replacement.

I removed the interior trim and headliner and now have the compromised vinyl off the roof. This is going to be a bigger issue since I found rust.

So let me begin with a couple of pictures:
IMG_2799.jpgIMG_2800.jpgIMG_2801.jpg

This is a view from the rear of the car at the back window. The blue painters tape indicates places with rust at the edge of the fiberglass bonnet.

I quickly checked both spots and thought things were good to proceed with limited additional effort other than a little rust removal.

Based on advice from smarter forum folks, I went back and spent more time with a different tool (awl) and pressed on all the rust areas and guess what:

IMG_2814.jpg The point of the awl is pointing at the hole I made when I pressed in that area.

This particular section where the bonnet meets the body is a single piece of metal; that is, it isn't a sandwich top and bottom like the hood. So that hole, which will be covered by the vinyl and the chrome trim, actually goes all the way into the trunk.

I cannot just leave it and I cannot fix it with the bonnet on it. So folks, this thread will detail removing the bonnet from my 87 Fifth Avenue and repairing the rust spots.

My current question is: Should I put money into getting a sandblasting machine (small) from harbor freight or northern tool? I figure the cost is low although the quality probably is too. Guess I should check to see if there are any other rust spots on the body.

My alternatives are: 1) use elbow grease and steel wool or 2) use 50 grit circles and small air tool and sand it out.

Then, since I'll have to patch it and I have zero experience in steel body repair, what do I need to know to do this correctly?
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