Did some googling and found this.....
Cement and plaster are alkaline compounds. They are easily removed from clothes, woodwork, your body and cars using distilled white vinegar (a mild acid). Simply soak a sponge with the vinegar and lay it on the cement spots for a few seconds. This will loosen the cement so it can be hosed away. It may take a couple applications to remove the cement from the car. Whatever you do, don't try to wipe the cement off with the sponge, as this will scratch the paint.
Wolf®
And the response......
Wolf,
Although it took a bit of scrubbing, the vinegar worked! I made sure to rinse my sponge after every wipe as to not scratch the paint, so it's going slow, but I'd rather take my time rather than scratch the paint. Some places are tougher than others. There's A LOT left to do, as some of the trim, weatherstripping, etc. needs to come off so I can clean underneath it. The 6” x 12" section I cleaned last night took about a half hour. Look at the photos in my gallery. Thanks for your help!! Now I can sleep at night…
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