[Richard]

Start with 325 wet on the clear, then 400 wet. Scotchbrite is not going to give you a look you will accept or long term adhesion. Plus, if yours is original paint, you are working with Imron which is notoriously hard to paint over. If you use the grits I suggest, you can spray over that and not see the scuff in the base layer. Do it by hand, if you see any color in the runoff then stop on that area, you are into the base, and it’s not very thick. Then prepare to wet sand the clear, starting with a 1000 and going to 3000. You will still need to buff with a polishing compound to make it shine.

The issue you are going to run into with the setup you are using and your climate, is the spray is going to dry as it is in the air. You will get a powdery looking finish. I suggest you practice on something else first before you try it on the coach. It is a HIGH price of commitment to rectify badly applied paint. That 2k clear is harder than Chinese arithmetic.

The key to painting auto is in the prep work, and the after work. The painting is the easiest quickest part. And one more thing, with auto paint you cannot cover a surface defect, the gloss only accentuates the imperfection.