when i bought my 05 lgt a couple of months ago, clay barring the whole car was one of the first things i did. it originally came from NY, then spend the last few years in SF and i'm not sure it was EVER clay barred..
the entirety of the cars paint felt like sand paper, and when i clay barred it, it turned the white clay bar, DARK ORANGE! probably from all of the sea salt in the air up in SF.. it was disgusting!!
6hrs later, the paint was as good as it could be, washed, claybarred, waxed!