3. Peter used Sherwin-Williams SpectraPrime P30 color surfacer/sealer, custom-tinted orange and mixed it in a ratio of 4:1 primer surfacer to hardener. Next, one part Sherwin-Williams SpectraPrime H38 hardener was added. Then UltraSolv US3 medium reducer was used to achieve the desired fill thickness. The ratio is 4:1:1. The combination was thoroughly mixed prior to being strained and poured into the priming gun.