Thanks GJ
I had some trouble making the screen, the original screen which I purchased was pre-coated and was supposed to be suitable for exposure in sunlight but was a dismal failure. I then stripped the screen and brought a kit from Amazon
Link here: (Hope that this is okay with forum rules as it is hopefully relevant to your question)
https://www.amazon.co.uk/Speedball-D.../dp/B0007ZHGWI
I exposed the screen as per the instructions which came with the kit using a photo flood lamp with "pie tin" reflector. The result was very good.
As for the printing, I had several goes, but when the print was not good I simply wiped the paint off with a rag and had another go.
It would be a good thing to use on those old wonderful Leak amplifier chassis for restoration in my opinion.