Length difference between front and rear axles on M923?

I've search the forum and net but cannot find the axle length (hub face to hub face) for the front and rear axles on a M923. Really what I need is just the offset between the two as I'm trying to understand wheel offsets when singling out the truck. I don't mind mixing steel and aluminum wheels, but want to know how the front/rear wheels will be to each other with different combos.

Mine’s longer...

There should be no difference if its a truck that is singled already. If you have duals on the back, all you need to do is flip the hubs and you'll be back to the same width.

gimpyrobb said:

There should be no difference if its a truck that is singled already. If you have duals on the back, all you need to do is flip the hubs and you'll be back to the same width.

Click to expand...

I dont think this applies to the 939series trucks.

On a M939, the brake drum connects to the hub with same studs that hold the tire so you can't flip. A duece brake drum uses the same bolt pattern as axle connection to the hub so you can reverse the hubs.

Rear hubs on M939, from the -24P, page 316, fig 315

I forgot to mention in my original post I don't have access to the truck so I can't just crawl underneath with a tape measure which is why I asked the question. I'm not THAT lazy.