A little bit of a surprise under the hood.......

Yeah, likely dual transfer cases or I think there was a splitter or overdrive or something, maybe Ranger overdrive was name? Orion also made something I think like that, dual case or something

 

I still remember when he came out walking next to his mini truck!!! Late 90s? Mid 90s?

 

When I was a kid my 1st car was a Jeep, put a Chevy 350 In it and it had

1 for transmission
1 for tcase
1 was an overdrive for each gear stick for transmission.
It was a high or low gear setting that determines the gears for the transmission if that makes sense. So my 3 speed turned into a 6 speed kinda.
Not sure what that setup was.

 

I had a 56 willys with 3 sticks. 1 for tranny, 1 for 2/4WD and 1 for high/low. Well 4 really, the winch control was a stick also. Fun little plow vehicle.

 

I believe it was a marlin crawler twin stick set up. An unreal set up overall

 

judging from the motor swap and the quality of the work its likely a standard dual case setup.
pretty sweet though I wish they had more pics of the radiator setup.

 

It's just a 2nd transfercase for ultra low gearing.

Probably a Marlin.
https://www.marlincrawler.com/transfer-case/built-units/hilux-gear-drive/dual-case-complete

 

Just like my '83 mud truck, except for, engine, frame, suspension, wheels and tires.... exactly like my old mud truck.