You will need to "outboard" the front spring hanger and shackle hanger. basically a platform extends out from the bottom of your frame, and the mounts attach to them. You can't move the spring placement, since the 'pumpkin" has the location cast into it.
There are many kits out there to this or you can make your own.
Driveshaft should be updated. You can swap out a yoke only, no big deal.
Pinion angle is different, as is caster. Build that into the outboarding, if need be. Steel shims could be used. I wouldn't go that route, though.
If you live in a state where "tire coverage" is enforced, you will need larger fender flares as well. If you run 12.5 inch tires this will prove difficult. I run 10 inch tires because of this. Axle is wider than CJ widetracks, but narrower than full size axles. Mine already had 5 x 5.5 lugs, not sure if scouts had those originally.
Dana parts are highly interchangable, if the spline count is the same.
You may need to swap all your soft brake lines, but that isn't too bad a deal. Scout banjo fittings are larger than later model CJ ones 78-up. Keep this in mind.
Front locking hub parts are hard to find. you may need to update the entire assemblies.
You should swap front and rear together, Short wheelbase "dualies" handle poorly and steering stinks.
Steering, I almost forgot. You will need a mild lift, 2 1/2 to 3 inch since the Scout is "high steer" and steering linkage is where your spring-under leaf springs will need to be.
You need a straight pitman arm. custom length steering arm. That's all the big stuff.