Vapormatic has a good reputation amongst the agricultural and tractor restoration folk. Wide range of colours, including a yellow that would be just right for Neil. I'm using it in Land Rover Stoneleigh Grey for my Pratt & Whitney model B lathe restoration slo-motion project. Impressed with the results so far. Primer is very thin but colour coats are high build. Easy to get smooth finish with a brush. Even for me. When it comes to painting its been alleged that my brushes come from Scrubs'r Us Janitorial Supplies. Which is perhaps mildly unfair. The P&W is wartime finish and has no filler under its original paint but two coats give a surface very close to that of a conventionally filled then painted machine. Helps that P&W castings are excellent to start with.
Also used Blackfriars QD90 which was some way on the good side of OK although I found it needed a month to harden enough to be properly oil resistant. Conventional white spirit for thinners. Brushed well but never tried spraying. Perfectly decent job on my Pollard 15AY drill and, prior to that, several other machines I no longer have. But that's no longer with us. Blackfriars do a metal paint which I'm assured is the same thing re-named but one wonders.
Clive