There are some vendors here that offer the "correct" grey, but yes the secret is in the prep work. My routine is first lightky scuff with a scotch brite hand pad, dish soap and thoroughly rinse, and once that dries either the Bulldog or SEM pretreatment. Also spray in several thin coats, allowing at least 30 minutes in between coats and let them completely cure for 24-48 hours before reinstalling.