Just to add a little to what has already been said. Wheel diameter is measured where the bead of the tire sits on the rim. Split rims have a taller lip around the edge than tubeless rims which sometimes makes them appear larger than they are sometimes. As already said, tubeless rims are generally 22.5” or 24.5” and sometimes 19.5” on lighter duty and some lift axles. Split rims, which ran tubes were usually 20”, 22” or 24”. 20” split rims and 22.5 tubeless rims fit the same spokes on spoke type wheels. As already stated both were available and even popular from the 70s - the 90s, at least around here. Most AMT kits are modeled after split rims including the Freightliner.