Hi, is it OK to leave a new galvanized rocker panel unpainted, or will it start to rust if unpainted? (I'd like to keep this car another 5 yrs at least). (Background - my 99 Dodge Caravan was rusting out on the passenger rocker panel, so I had a local body shop cut out the panel and replace with a new galvanized piece, looks good. But the shop was really busy that day and didn't have time to paint it. I don't really care much about the color, but I want to try to prevent rust from recurring there. Is it OK to leave the panel as-is, unpainted?) Thanks.