There is a disc brake option, but it is not a simple or easy one.. well it is somewhat simple in plan, but not easy.
Check out my webshots pictures (link below), there is a folder detailing the conversion to disc brakes for a 1.5 and 2 ton, and I actually put the axles under my 1 ton at the time, now the same axles are under my 2 ton.
This method even uses the correct bolt pattern for 1.5 and 2 ton, so from the outside looks mostly original.
In short I used newer axles (disc for front and rear) and the front axle needs to be cut and narrowed.
Not shown in the pictures is a way to use a new front axle with the original steering. To do this a P30 front axle is what to start with, while I used a 3500HD axle and added PS, otherwise the process is the same.
Hope this helps,
Grigg
