I got a 91 TC2000 but with a different drivetrain that you have. I have the 5.9 Cummins with an Allison 545 (I think) and 4.33 rear end. It's a great drivetrain, it's powerful and gets decent mileage. When I got it it topped out at an indicated 57mph, I had Jason (fellow skoolie member) turn up the governor and now it goes almost 70mph (indicated) - which I found out with my GPS is 10% slow - so 60=66 70=77 ect...