Converting Harvey into a DMU

Wow, that's quite impressive. I don't have an airbrush, sadly, and I don't think I can get away with buying one (compressors are fairly expensive, and I promised my wife to be this would be a low-cost hobby).

I'm thinking of using the Halfords grey primer as suggested, and Humbrol Brunswick green spray in a can for the body. Depending on the shade of primer I may just leave the roof in primer grey. We'll see.

Should I sand the 'Clarabel' face off the carriage ends?