i'm looking for what the following trans might have come out of. the tag on the passenger side reads
459
CO-69-17725

thank you mike

Look here:
http://www.teufert.net/trans/t-400.htm

69 is Model year
17725 is unit number
459 is day of year (start counting from 1-1-68)
CO=??
I do show a CQ for 427/335
Here is a general Chevy list by engine

CA = 350, 396, 400 / (265, 325)
CB = 427, 454 / (390)
CC = 396 / (325)
CD = 327, 350, 400, 402 / (235, 250)
CE = 396 / (350)
CF = 402, 427, 454 / (335)
CG = 396, 454 / (265)
CH = 396, 427 / (390)
CJ = 396, 402, Truck 1/2- and 3/4-ton / (310)
CK = 327, 350 / (300) Corvette
CL = 427 / (400) Corvette
CM = 307
CP = Truck 1-ton
CQ = 427 / (335)
CR = 454
CS = 454
CT = Truck 1/2- and 3/4-ton
CW = 402
CX = 396, 427 / (375, 425, 430, 435 & COPO)
CY = 350, 396, 427, 454 / (245, 255, 425, 450)
CZ = 350 / (L-82)