Marty shared this customized CJ-6. He confirmed this was built in Pennsylvania. Both rear axles are drive axles, though one new carrier bearing is needed. The large side windows suggest the Meyer hardtop was modified, too.
https://twintiers.craigslist.org/cto/d/coudersport-1974-jeep-cj-6×6/7433296490.html

“his is a 74 CJ5 extended to include a third axle. Runs rough at the moment but drives amazingly well. It is powered by a 79 small block 350 which makes this Jeep scream down the road. Very well built all original look steel interior and exterior no fiberglass. Has a stretched and modified steel hard top wrapped in vinyl and a steel half cap included but not in great shape. Also includes the tan bikini top for warmer driving. In the opinion of mine and others (mechanics) this is a very well built rig and can be left as is with minor work and still a one of one head turner in the world!! Needs a carrier bearing on the mid axle rebuilt to drive the rear axle and with that is a live three axle Jeep. Will consider trading for; Scouts, Range Rover, Land Rover, Land cruisers 43,45,or 47 Ford Bronco, Jeep CJ6, CJ8-Scrambler, pretty much anything old cool and definitely 4×4!”