I've done some reading for you, and it seems most stocj springs can't be desambled. The RS24 for example can be desambled verry easy.
Some other shocks should have some sort of disc on the top and if you get that disc out, the spring comes loose.
So basicly, I think it will be verry hard to get the spring painted.
Another remark if you paint the spring, won't the paint "break" from the movement?