It's an odd vehicle.
It looks like something that the desert racers' builders would make to pay the bills.The truly talented pirate 4x4 people.
At first I thought it was just a JK8 with a GM diesel for some reason.
Using a GM 6.5(out of production for over a decade) with a 4l80e would seem to be an odd choice.Any Humvee mechanics should have no problems with it but it's not terribly powerful and it is late seventies tech.
The 6.6 is,in some ways,an even odder choice.The Isuzu V8 is bigger,heavier(a couple of hundred pounds IIRC),gets worse fuel economy and is vastly more complicated.The six speed Allison is a good trans-no qualms there.
The dash isn't impressive.Three different gauge manufacturers for common gauges.Generic knobs and switches all labeled with a Dymo.It looks like the builder went to NAPA,they didn't have everything,so then they want to Autozone and got the rest.
The interior appointments(seats,GM steering column,drag race/offroad shifter,the t-case twin stick)all look like current build up parts for a good trail rig.
IIRC,Dynatrac is out of Utah as well.The front is a Dana designed axle,I'd bet the rear was too.
I'm still curious about the frame though.That lh front corner that's visible looks like a Jeep JK.It doesn't make sense with the GM engines though.Cornfused.