I have a 55 chevy belair Coral/Gray two tone to paint this spring. The only CORRECT color I can find was by a body shop in Florida that used BASF products (they used glasurit) and have provided me with the formula. I am unable to source glasurit 55 base in the northeast, and my closest BASF store claims they have a formula in Diamont that will be correct, no way to cross formulas from the glasurit. Will SPI work over these bases, and can I get some glasurit somewhere that can be mixed to my custom formula?