In case the information at the links that I gave above to the oldGMCtrucks sites are confusing:
B228480406 Engine Serial Number
B = +0,005 overbore, -0.010" off the crankshaft main bearing journals, and standard crankshaft rod journals
228 = 228 CI GMC engine
80406 = sequence number
http://www.oldgmctrucks.com/photos/EngineSpecs_Pg1G.gifhttp://www.oldgmctrucks.com/page0010.html152 22 C 5254 Vehicle Serial Number
15 of 152 = 3/4 ton
2 of 152 = 125.25" wheelbase
C = 1953
5254 = sequence number in 1953
http://www.oldgmctrucks.com/page0015.html