I have the same blue on my calipers.....the paint has lasted really well...I went through one season of winter already and only had to touch them up a bit - and that was from the shop putting on my rims that made the scratches - argh. You can put that stuff freakin' everywhere...it's made to withstand alot of heat and weather!
since it was chrome i just used the paint, you are only suppose to use the base if its not chrome, its like shooting candy on a car u have to have a base coate then the transparent paint. thats all this is. i scuffed the chrome up lightly so it would stick.
the back one i pushed it slowly up and slowly pried it with my fingers be carefully not to pull up to fast, the front well thats a different story i broke off the clips, i think everyone breaks the clips, then i pushed up on it also the front was alot harder to remove but just be slow and it will be fine
If you don't use the ground coat (silver) under any of the duplicolors, you will not be able to achieve a nice metallic look, it will be rather flat and much darker than the brilliant blue, red, purple, whatever you used.