The 702 V12 was in GMC trucks from 60-65?.
They were offered in a COE and a stub nosed truck. Also in some Walter snow plow trucks.
Many of them were used on irrigation pumps in the Midwest.
I don't know if they were offered for sale as industrial engines any later than 65, but I am guessing not.
Some great info on the 702 can be found here:
http://www.6066gmcguy.org/TwinSix.htm Grigg