So after a recommendation, I gave mr clean a try..
http://www.homemadesimple.com/mrclea...ry/index.shtml
Not too expensive and I was really surprised by the results. It has perhaps made my car cleaner then it has been in a long while. It might just be worth buying the soap. The no drying part comes in as an added bonus.
I only wish I had time to do a coat of Zaino, it would have been perfectly clean base to start with.