043443T255XA

043443 = 42443rd truck out of that plant that year (that series?)
T = Tonawanda, NY engine plant
255 = second series 1955 Task Force truck
XA = 3600 (3/4 ton) truck

Someone will correct/clarify if necessary.

Tim
1954Advance-Design.com
1954 3106 Carryall Suburban
1954 3104 5-window pickup w/Hydra-Matic
The 216 and early 235 engines are not "splash oilers" -- this is a splash oiler.