The rear axle is the easier of the pair to fit:
You'll need to shave all the brackets off the -60, weld on new spring perches in the appropriate position, get new/modify existing spring plates(-60 will have bigger axle tubes then the -35: U-bolts won't fit, and stock spring plates won't fit the new U-bolts) adapt or replace brake lines, adapt the E-brake(if desired), and get the proper sized yoke or a adapter U-joint.
The front axle is a pain:
There is NO stock axle, other then an XJ/MJ/TJ/ZJ -30 or hybrid-44 that will bolt into your truck. Assuming it is a driver side drop axle(some 4wds mount the pumpkin on the left, some on the right. XJ/MJs mount on the left/driver's side)The first order of business is to get a control arm mount on top of the pumpkin. This is cast into the XJ/MJ/TJ D-30 housing, and can not simply be cut off and welded on to the new housing. 'Couple companies make trusses that carry the mount, or you can fab your own.
After that's sorted out, the rest of the control arm brackets/spring perches/shock mounts/track bar mount have to be cut off the -30 and welded on the -44. A more expensive option is to call a company like Currie or Dynatrack and buy a set of brackets. They're expensive, but already cut to fit the larger axle tubes.
The other option is to re-design the whole front suspension, using radius arms, 3-link, leaves, custom 4-link or whatever. This is actually a lot more work to get right then trying to get all the brackets lined up and welded to fit the stock geometry suspension.
"Never attribute to malice that which can be adequately explained by stupidity, but don't rule out malice."
My other car is also a Jeep,.. and so is the other one,.. and that one too. How many do you own before it's "a herd" ?