I am doing a comprehensive rebuild on Goose #4 (see ridgwayrailroadmusuem.org) and studying the history of the use of the GMC 361 engines which were installed about 1947. These are narrow gauge rail busses. My problem is identifying the age of the engines. The serial numbers are as follows.
#4 = 3615654
#5 = 3617751
#7 = 3614364
Can anyone help me with approx dates.