The colours changed - I know nothing about series 3s (and I'm still playing catch up with series 2a's). I only know that for my series 2a 1965 diesel engine it was meant to be duck egg blue.I was going to paint mine with the paintman's cockpit green my S3 is going to be bronze green, what colour are they meant to be? Standard petrol by the way
Which ever colour you choose if you're putting it on an engine or parts that will get "engine hot" then you need to use a special engine paint. These usually are used straight on to bare metal - no primers.