I'll get some actual chassis measurements off an 80s one-ton and a 90s one-ton in the morning.
Measured the early 90s 3500 (no vent window style),the chassis measured 43" wide(outside to outside) at the rear wall of the cab and 39" inside to inside at that point.The chassis stays parallel under the cab and widens at the point of the firewall.The chassis narrows down behind the cab toward the rear of the truck.
I'll get measurement of a mid 80s 30 series truck tomorrow.
