New process for painting. So I talked with technical support at Nason Paint and they said I could easily paint over paint. So new process is:
I spray he center color which is grey. it will be the 2 inch strip.
Then I tape over the 2 inch area of the grey that I want to keep.
Then I spary the white and blue. I never have to lay tape down along the seam line again. Just once. I was having to do i 2 or 3 times which was tiring and prone to errors.
I scuff up the grey overspray with 400 but Nason told me to use 800 or higher so I will in future.