Actually, this is the second time I built a gravel train. Back in high school, (1981) I built one and added lights. Unfortunately that kit was destroyed. When I was in the Army.
This was an attempted to build an updated version of the old AMT kit. I went to a local gravel yard and took photos and measurements. I think I added a scale 8 inches to the top of the cab and 6 inches to the bottom as a skirt. I widened the radiator and lengthened the hood. This was based on on actual truck.