Help With CLR!!

[Jaredchevyk20]

Hi, i have an 86 k20, the top of the bedsides has surface rust. I have read threads on that clr stuff and im going to give it a try. Basically im not going to start restoring the truck for another year or so. I dont want the metal to pit, if i make a bucket full of water and pour some clr in it and then scrub the truck with a scotch brite pad, rinse and be done, can that harm the metal at all? just sitting like that after i rinse? Thanks