There is one rod brace that goes from the frame to the outer rear wheel opening. That and the running boards would basically locate the fenders. I believe the second bolt hole from the bottom on front and rear of the fender mount flange would be at the same height, as they line up with the bed angle on the bedside and bolt thru them just above the wood bed floor. I don't have the height of that point above the frame, but could probably track it down from my bedsides in the garage.
