This has a large tank on the back. Seller believes this was in the military. There appear to be a couple data plates on the dash, but otherwise this looks civilian to me. Thanks to Brian for spotting it.
http://willysforsale.com/ads/military-jeep-fc170dw/
“Military model Jeep FC170DW. Late 50’s to early 60’s model. 1 ton – dual rear wheels, L6-226 engine, 4 wheel drive. No tag or title. Engine runs, new shop built fuel tank. New fuel line. Fitted with large water tank. Needs restoration. Would consider trade allowance for Saturn overdrive or Ramsey PTO winch and drive for my L6 226 pickup.”