Working on a '90 K5 blazer for a friend. With the engine out I was cleaning up the engine compartment and something didn't look right. On the pass side the frame has the quad shock mount riveted to the frame but truck doesn't have the quad shock option. Drivers side doesn't have the bracket nor was it ever there. Apparently the inner fender wells are different for single vs dual shock option. The frame mounted bracket rubbed the inner fender until it wore a groove into the fender and it cracked from there. There is an indent in the fender well that if cut out at the part line would offer clearance for the bracket. Now that bracket has been rubbing since brand new and the truck has 198K on it! It HAD to be noticeable when new with minmal wind/road noise of a stock truck. And no one ever noticed it to trim the fender out or remove the bracket.