Your Welcome ! Yeah I would not use soap and water. If water gets underneath the Aquaplas it can create some serious problems with refinishing and repainting them. As long as all the loose dust and dirt is removed with compressed air don't worry about the color, you will address that when you repaint them. Use the isopropyl alcohol but sparingly. You are really only addressing the spot repair on the horns and not the entire horn.. One other thing you will run out of space quickly on this site for your pictures.. I suggest using a free picture hosting site like Flickr or something similar. Just do a little research for the right site.. One day it's free the next day you have to pay for them.. Case in point is Photobucket ! That site tried to extort me to get my pictures back.. I will never buy anything from that company...But I am sure you can find something suitable. The photo hosting at our site is very limited...