This does appear to have an MB/GPW frame (see the rear shock mount), but much of the rest looks civilian.

https://medford.craigslist.org/cto/d/1942-willys-jeep-ready-to-roll/6739248633.html

“Powerful V-6 Buick Motor Conversion done right. Aluminum Radiator, Electric Fan, Doors not shown but included. Oversize Cleat Type Tires, 2 extra gas tanks. Towbar and extra hitch. Road Light Bar. Personal Jeep owned many years by a particular owner. This is a rare early production model built in 1942 by Willys for government issue. Painted in Navy Gray, recently serviced and needing nothing to drive away!!”