This has turned into a JB Fab advertisement! Which I fully endorse!
But to answer some of the OP's other questions,
Was it easy? Yes and no. The J shift is pretty easy but I think you have T shift, correct? The T shift is more complicated if you want to be able to shift front and rear independently. This requires some internal TC work. If you don't need the front and rear to operate independently then twin sticking a T shift is easy. Are you expecting to be doing front digs on the trail?? If not, you probably don't need fully independent operation. My 72 has JB Fab twin sticks on a T-shift case with no internal mods. It make shifting the TC much easier and glancing down I know what range I'm in. This is not a trail rig or a Bronco I take on the trails very often but I still really like the twin sticks.
Special tools? I only needed a 3" cutoff wheel to cut the access hole in the tranny tunnel. One other thing, my body mounts were collapsed and I did not have room to install the twin stick linkage. So I added the WH 1" body lift. This made it very easy but if your body mounts are good you should not have any fitment issues.
Is it worth it? Twin sticks are a relatively inexpensive mod, so yes, to me, well worth it.
My trail rig has a J shift which is set up to shift independently which I use on the trail.