2redrovers

Someone with more paint experience can correct me if I'm wrong, but as I understand it cold gal / zinc isn't what you would call a stable surface. The nature of zinc as a self sacrificing agent to prevent rust by converting to zinc oxides would mean that paint layer over the top wouldn't get the solid anchor hold it needs to bond permanently. Eventually as the zinc began to break down under the paint, it would create powdery oxide layer and allow the top coat to bubble and peel off. It would happen slower under paint than an exposed zinc surface but would still happen.
 
I believe you can use turpentine based paints over zinc rich coatings, but it's still not truly long-term adhesion.
 
(no offence taken if I'm incorrect)

Sedans are harder to make sleek but personally, one thing I don't like about XCs is the window line at the back door to the pillar. It's more squared off like an early Granada (an attempt to lead-in to the square Falcons) whereas XAs and XBs have the coke-bottle hip line, much more curvy and fitting with the rest of the car. I find the quad light front more attractive than the rectangular one.
 
Depending on how extreme you want to go, you could lay back the windscreen and same for the rear window. Rear pillar could be thinned down at the top to suit the laid-down glass but keep the same line on the door frame. Side glass could be a problem on the front though, maybe get some rear door glass, swap sides and install in front with custom front quarter glass like a smoker's window.
 
You could look to some exotic European sedans of the era for inspiration, like the Maserati quattroporte or De Tomaso Longchamp, even Jag XJs.
 
I'd delete bumpers and fab custom bodywork to fill in the gaps, then put some more delicate ones on that wrap nicely around each end of the car, like on an E-type Jag.
 
Cut out and fill wheel arch swages and re-profile the rear to match the front. (70s Falcons look like bum-draggers)
 
Overall I think it could be a very handsome car if done tastefully and with period styling cues.

That's pretty much what I thought about all of it except you explained it very well (much better than I could)... Cheers redrover

With the old cars, further back you go the more likely that it's enamel paints. You get the nice patina from enamel because as it ages and degrades, it powders up with a chalky oxide an slowly falls away. A lot of metals were used in oxide forms to generate the pigments and flow characteristics of enamel, some of which I'm sure were zinc which would have helped protect the metal along the way.
 
Later paint is acrylic and then 2k, which will go porous as it breaks down, allowing moisture to penetrate. Because the paint is more like a plastic sheet covering the panel, it keeps its structure longer, trapping the moisture under the surface and allows deep rust to grow. Eventually the paint looses its ability to hold together and flakes off instead of powdering off.
 
I think the high temp paint is more like an enamel base too. When you add in the heat cycling I think you'll find that the cold gal isn't behaving the same way any more and would have a different bond and degradation effect.
 
When they say it's not a suitable base, it's not that it won't work or that it won't work for a while, it's more that the results are not able to be guaranteed to give you what you want. There's a lot of variables and sometimes it will work ok, others will be disastrous results that haunt you no matter what you do with it.

Someone with more paint experience can correct me if I'm wrong, but as I understand it cold gal / zinc isn't what you would call a stable surface. The nature of zinc as a self sacrificing agent to prevent rust by converting to zinc oxides would mean that paint layer over the top wouldn't get the solid anchor hold it needs to bond permanently. Eventually as the zinc began to break down under the paint, it would create powdery oxide layer and allow the top coat to bubble and peel off. It would happen slower under paint than an exposed zinc surface but would still happen.
 
I believe you can use turpentine based paints over zinc rich coatings, but it's still not truly long-term adhesion.
 
(no offence taken if I'm incorrect)

They couldn't drive past a Krispy Kreme without stopping and created an uncontrolled desire in the driver to pull over any nice lowered cars "just for routine checks"

Bahahahaha!! I thought i'd been called every name under the sun at one time or another.... seems i was wrong!
Can i use that one Greg? There's a heap of 'wankpuffins' around here, they just don't know exactly what they are yet and i feel the need to tell them. lol.

Here at IolzFalcon, we have a tradition of slagging off any spammers that happen upon this otherwise righteous place. I felt it was my duty to do such, but alas, the original offending post was promptly removed by our diligent moderators, leaving my otherwise legitimate reply to these (self-fisting) goat-felchers instead looking like an unprovoked jibe at your otherwise fairly decent self xwroo. I do apologise...
 
But has been entertaining nonetheless