The telephone trucks were all Signal Corps items.
The earth augur was a K44, and on the same chassis you could get the K43 pole setting truck. I had one, and it eventually morphed into the blue cargo truck on 'Darling Buds' that now sits looking sad at Beltring.
If Geoff looks the other way for a minute, I'll mention that this GM product has it's own forum, dedicated to GMC, DUKW, and US Chevrolet, although to be fair there are more southern hemisphere members in here...
http://disc.server.com/Indices/183912.html
Gordon