This MB/GPW was reconditioned in California. The main two companies working out of California were Bechtel and Moore, so it was likely one of those two. The jeep has the plate on the dash, but I can’t make it out.
“Willys Jeep 1942 original, 12v electric runs good, new tires, no rust sand blasted and painted 30 years ago stored covered or indoors, chains included in 50 cal amo boxes, re manufactured by company in Ca 1946, bought of my uncles farm 40 years ago used for hunting many fun years”
http://saltlakecity.craigslist.org/cto/5698345364.html