First post- better make it a good one!

If you got for as cheap as I think you did the 4x4 chassis is worth a bit. Especially the steer axle…… T- case still there?

 

If you really think you will be seriously needing that 4x4 i would look into geting a 15 speed tranny with deep reduction. Allisons are great transmissions... But in my experience they are very slow under load.

 

School buses go for cheap once retired and are normally pretty well maintained, plus there is a ton of IH out there to pick from. DT466 would be a good choice, IMO. Most are all autos, too.

 

If you are leaning toward Cummins. I would lean toward the ISL over the B. More- higher horsepower and torque options.

 

Don’t do an isb, at least an ISC or ISL, see what it had in it for a trans, the dealer can give you exact model and serial numbers of the trans. Getting a trans for it may be an issue, seeing it has a transfer case attached to it unless you are going to use an unattached one.