wing vent interchange

[3x2GTO]

I installed the vent windows, arm rest and bumper guards today, found some damage to the small center brackets that mount the front bumper to the frame horn. I knew the truck was wrecked years ago and took it for granted that they had fixed it right. They didn't just hammered out the brackets and they fit and look terrible, going to have the frame horns checked while I have it apart. Any difference between C or K brackets? My truck is a K30, are 1/2 -3/4 brackets the same? Going back to the yard again ASAP.