Looks to me like the difflocks have been converter to air???
Those manuals will do the trick, I must admit though they go very little into any technical detail, no shimming up info etc.
Never thought about moose but I've always wanted to go boar hunting in Norway, have to be very fit i believe?
Working is what mog's we're built for

I'm currently restoring a 1965 411 for a customer and it's having the lot done, will be very posh when it's done, but won't be worked at all.
The blocks under the springs are not standard, if it is for clearance for the engine, I would keep an eye on your torque tube angle. it could be that when offroading it will become too steep and cause damage to the torque tube coupling/drive shaft/dampers. Ideally the blocks want removing.
The chassis plate tells me only what you already know I'm afraid, it's a canvas top 411 long wheel-base.
I would think looking at the back body it has a u600 body on it, it looks very wide, I could be wrong though.
My dad (moose on here) has size 12-13 feet and drive's his 411-118

Do you have a closer picture of the rear linkage? the power arm doesn't look standard.
Cheers, Brian