As long as it is a standard 60 then any lp60 gears will work.
Yes the 78 ford stuff is the longest short side there is. If you really dont mind putting in the work you should be able to stretch your short side and cut down your long side to match a 78, then buy some inner shafts. Yukon replacement shafts for that model are pretty cheap. Not the best shaft on the market, but in a 35 spline with a stock 4.0, they should suffice.
Hi pinions have little to do with strength when dealing with 4.0's clay.
When you get into custom suspension and long travel, that is where they really come into play.
As soon as you flush mount your lower control arms, a lp driveshaft is the lowest link to the ground. Where as a HP is still protected by the arms.
Getting into 14 plus inches of travel, the difference of 2 inches of pinion height can be the difference between shaft bind, or no shaft bind at full travel.
At the end of the day a hp is stronger, proveides better clearence, is more reliable due to better clearence, and provides for more suspension travel.
All in all, they are just better.
Considering how much work it is to install a 1 ton axle into any wrangler I'd never recommend doing lp unless you absoutely had to.
That axle pictured has been running in my rig for a couple years now Impact. Im building a set of them for the wifes jeep currently. If you have the patience, you can peice by peice a 9" over time.