not quite guys ... the number/letter combo started in 56, the 55.2 just had a single letter, and that setup was the series designator for paperwork like the vin, which doesn't indicate the model ... 3A or 31 both designate a 114" WB 1/2T, but might still be a pickup, panel, etc, which will be the next 2 numbers, which was indicated on the trim before 58 by '3100', like saying 31xx
jhaa_lives - in 58 they dropped the '00' for trim and advert purposes, the 38 was the series, and 38 series included: FF Cowl&Chassis, Cab&Chassis, PU Step Side, Panel, Stake, or W/S Cowl&Chassis - the next 2 numbers indicate which of those models
some 56 up trivia for ya:
31xx = short 1/2T
xx03 = chassis/cab
xx04= pu
xx05 = panel
xx06 = burb w/ barn doors
xx16 = burb w/ gate
xx24 = cameo
xx34 = fleetside
Bill
