Yes I'm aware there is a massive difference between 1st Gen and all the others. However the mid plate bolt pattern is the same. In 2017 when researching a stronger better raito OD transmission than the non lockup 46rh capable of handling power above stock, thermac crossed my sights.
I talked to an engineer at thermac he assured me there Magnum XL 2.66 transmission would handle any tuning I did to my first gen including a p-pump and twins swap ,however, nobody to their knowledge( Circa 2017) has devised an appropriate mounting solution. He went so far as to say if I prototyped a bellhousing and Associated parts they would be interested in purchasing the kit rights as the Cummins market is massave and all have the same mid plate bolt pattern.
Yes a thermac is behind the viper V10 which is the V8 bolt pattern not the truck V10 / diesel pattern.
Problem I had with the NV 5600 or the G56 is there both are single Overdrive just more gear between Direct and 1st as well as power limitations, let's face it 85 miles an hour a 0.75 OD would be at Redline with my 2500 rpm governor and 3.55 gears running 31.7 D Tires for me this was a step in the wrong direction Bonneville Salt Flats are all about gear ratio and TQ . I finally decided on a built Allison 6-speed with a 2100fttq /700hp warranty.
3.20 first 12: 1 with torque converter per the TCM OBD2 read out , 0.71 5th, 0.61 6th now cruise @ 85 =1952 rpm 14rpm below peak HP per the dyno on the old trans.
I understand many want the manual transmission for stopping power. In April I went to Pikes Peak on the way down I only used the brakes in a few of the hair pins, I stop at the halfway down brake inspection point, the front brake rotors where for registering 80°, @300° they write you a speeding ticket.
Dreem Big Chisel Down To Reality