Yeah,Pat has it in one..ALWAYS repair from both sides if at all possible..You do get a better grip on SMC if its sand/grit blasted,plus,I use a small amount of gelcoat,and when I catalyze the brew,I put a few drops of cobalt in too,,,that makes you work a bit faster,and helps with the heat and bonding.I do this for a living,and have repaired a lot of Mack,Western Star KW,and Pete fronts,in fact,I have another W/Star coming in tomorrow,,hey,Dgas56,just flop ya Vette into an A4 sized envelope and post it to me,,Ill sort it for ya...