Hey guys I know it does work for a long time and that I should be welding new steel in. But I've already got the paint really cheap, it's half in bog and primer so I need to finish it before I start driving it again. Now do I want to do this properly? No. It's already been bogged and bogged and bogged. I just want to blow it over so I can drive it without being fisted by the police. While I look for a more long term shell. Or a SSS shell if I can't find one that doesn't need big work. Is there a trick to getting a little big longer out of it? I've rust converted all the bare steel and sanded most of what I could out. And I ended up using quick steel fuel tank repair through the little holes it had. Which wasn't many at all. Is there a type of rust guarding primer that you can still get a quality finish over? I've been told it never looks right once it's on top it. Any suggestions would be appreciated.

First up. I'm never a fan of doing anything other than properly.
But... if I were going to fix up and blow over a car. I would probably sand and treat the rust as best as I could. Spray POR15 or equivalent on the bits that were prone to become rusty (Even though it says NOT to use it AFTER you've treated the rust).
Then on the rest of the car, prime with EPOTEC 408. Which is a zinc rich 2 part epoxy primer. If you go POR15 on first or the rusty bits, then give it a dust coat of primer after it starts to go off and become tacky, in about 10-20 min or so, that dust coat will let you primer it properly later.
Then prep the car as per normal with Hi-fill or spray putty.. Block it out flat Then top coat.

Dodgy as, but should work for a little while.

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Ongoing Project: 1972 Datsun 510 S13 SR20Det. http://ozdat.com/forum/viewtopic.php?f=33&t=17898
New Daily: D22 Navara (The new workhorse)
Retired 12/2016: MY98 Subaru Impreza RX
Previous Car: Restored Green 1972 Datsun 510, Hot L18

If its at all possible, get in behind the repaired area and flood it with rustproofing (fish oil / tectyl / etc).

ie inside doors, sills, inside the bottoms of 1/4 panels and so on

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1970 ex Group A Rally P510
1971 P510
1972 180B SSS
1965 SP310 Fairlady
1966 SP311 Fairlady

Yep. Fish oil is your friend too!

_________________
Ongoing Project: 1972 Datsun 510 S13 SR20Det. http://ozdat.com/forum/viewtopic.php?f=33&t=17898
New Daily: D22 Navara (The new workhorse)
Retired 12/2016: MY98 Subaru Impreza RX
Previous Car: Restored Green 1972 Datsun 510, Hot L18

Yeah man I've painted cars before used to do machinery painting for a living I'm just not really an expert of doing things dodgey. But in all seriousness it's in the bottoms of the doors because the last blokes resprayed it and bogged the drain holes in the bottom of the doors. Bottom of the rear guards round the corners of the bottom rear apron. It's not bad but the more you sand the more bog you already find. It's a vinyl roof so I know it's full of rust underneath it. My point of view is get it ten metreable just for cops. I will do one properly at one point but to go over the entire car almost back to bare metal and weld in patch panels on just an aussie delivered 4 door in my opinion isn't worth it. It'll be cheaper to find a nicer shell when one pops up and transfer everything. Or spend all those hours fixing rust on a sss shell.