Frame jig, nice to have, 30 Days ? Work Quickly

I think for the trouble, the 9" Jim Mazola lift would
be easier, uses stock mounts (reversable) and moves
the driveline down.
Problem is your ground clearance is not getting better,
bigger tires for increased clearance seems to be the
only way to recover from this, then you start taking out
CVs and Shafts.
My personal preference is to get as much out of the suspension
and leave the front diff up to clear the boulders
A lift should provide 3 functions,
(1) To increase ground clearance
(2) To make room for bigger tires
(3) To increase articulation
I laugh at all the wanna be Chevy "Pre-Runners"
I see jacked up as high as they will go, does nothing
for articulation, fact is you will get stuck by over lifting
the suspension, because of lack of down travel ability.
If the tires cannot follow the terrain, how can they give
you traction

Lockers are great, but places I get into
if you can't drive all your wheels, you ain't gettin up it.
Some loose and steep situations need all available traction
and airborn tires can't catch enough wind to do the job.
If the lift you are building does this

Pics please, a sketch will do

That's the Wild opinion