Paint: How to clean this up and fix it?

I don't want this to be perfect, looking for a good 10-footer.  Preferably with spray cans?

DA sander to knock down the rust and take up the loose paint, feather it in to the existing, then primer and lay down some paint?  Wet sand after?

I would DA, Ospho, prime, and paint. 

Ahh, white paint.  Glorious.

Anything less than a strip and repaint is temporary, but ... I walked out the front door to take that picture.

Buy a can of white Tremclad, and some sandpaper.  Repeat as required.

Trust me on this one.... you could go to a top-notch body supply house, give them your car's paint code, let them mix you a pint.... and it will stick out like a sore thumb.  Whites are SO hard to match.

If you're really good with a rattle can, just get a bunch of Duplicolor cans and spray the whole roof.  Your eye will be tricked into accepting it as just a different angle instead of having three spots that look like dookey.

When you mask the edges, leave the tape curled up instead of doing a hard line.  The curve of the tape will do a 1" feathering for you.  Knock it down with 2000 and polish.

Caveat:  I've done this a dozen times, and every time it looks like a 5-year-old did it because I absolutely suck at body work and paint, but if you have a modicum of skill, you can make it pretty.

+1 for stripping the roof and spraying the whole thing. Trying to feather out those spots will probably quickly demonstrate how fragile the paint adhesion is. 

I've had good luck with Duplicolor, but by the time you buy enough, plus the clear, it's probably cheaper to buy a quart of cheap single stage, primer, and a spray gun. (Assuming you have access to a 10+ gal compressor) With Duplicolor, I'd expect 5 cans of color, and probably 8-10 cans of clear to get a decent result. I used 2 cans of color and 2 of clear to do almost half of the roof of a crew cab Dodge, but could have definitely used a lot more clear to get a decent wet coat. 

Wet sanding will need follow-up with a rotary buffer. If you have access to one, and you're willing to wet sand, you could brush/roll on some single stage and get a really nice finish result that way as long as you build it up. I've seen some guys (Like Duster) buff Rust-Oleum, but I don't have any first hand experience there. 

I'd also treat the rust with ospho. 

I've found the basic NAPA Martin-Seynor single stage to lay down really well. The HF HVLP guns are fully acceptable.

As for matching, just spray the whole roof in a different color like black. Now it's a limited edition:) Is that a P71? A black roof is on brand.

The extra holes in the roof and trunk are pretty typical for a p71. Good suggestion to not try to paint match it. Black would look good, if you don't mind the solar oven effect.

My vote is to do the whole roof. You could go with single stage paint in white of some capacity (fleet white, gloss white, oxford white).

OK.......smart ass answer , 

Vinyl roof like the 70s cars......

Treat the rust.

Mask the whole roof, scuff and hit it with rubberized undercoating.

Vinyl roof on a beer budget.

Had similar issues.

Scuff sanded with 320, shot it with a rattle can called it a day.

Wrap the roof black. 

Unfortunately, Mr asa, whole roof. Blending is ok if you're a pro, but ive never had a diy blend job work out. Panel painting is generally the reccomended repair route as well even for the professionals whenever possible. 

Hell, you can roller on rustoleum if need be. Don't forget your hardener.

The center of the roof here is 5 year old Duplicolor that's been in direct sun 95% of the time. In Texas. Color match isn't great, but it passes enough for $30-$40 of rattle can paint off the shelf.

It's straight out of the can, no sanding or buffing and not applied as wet as I would have liked. (Probably another half a can would have been perfect.)

I think JThw8 has laid out a perfect example of how to deal with this.  I'd try applying some kind of rust treatment on the bad spots after sanding down the whole center of the car top and then a couple rattle cans of Rustoleum Appliance White epoxy.

Just to be clear, you don't really want to "rust convert" the rust, you want to eliminate it.

Sand / wire brush the rust away.  The Ospho (phosphoric acid) will act as a sort of "soap" for any minor remaining rust, allowing you to wash it away.  It will also etch the metal making it less like to rust and of course clean it.

Only put paint on entirely clean and etched metal. Bubbly paint will likely result if you do not.  Be aware that primer (not epoxy primer though) is very porous and metal will rust through it so don't leave it in primer for any length of time.

I am definitely not interested in vinyl wrapping at this time.  Probably just going to tape off the whole roof and hit it.  

Id like to get rid of the plugs in the top as well.  JB weld, maybe.