PPG has a good product called DP and its great for what you're working on. First use dx 103 to clean the glass then apply one full wet coat of dp. Allow the proper flash time then apply two or three coats of k36 primer surfacer and allow to dry then guide coat and block with 240 grit until you you only see the grey primer.Then guide coat again and block with water using 600 grit. From there reclean and paint. When painting basecoat/clearcoat apply basecoat until you have proper hiding, then apply the clearcoat. Three if you plan to buff. Hope this help.
well to begin with you want to use a dp primer which is a primer sealer...... when you primer you only want two to three light coats.... you don't want to see any fiberglass through the paint though.... when you're done you want to use a 220 grit sandpaper to lightly sand the top coat of the primer..... when you get to the color stage you want only two good coats of paint.... the clear you're only gonna want two coats there too or the paint thickness will be too much.... if you go past the paint limit your vehicle will be heavy from the amount of paint on the body. hope that answered your painting questions