This is all a very interesting turn you're taking in (seemingly to us anyway) mid-stride.
First, you don't know what you ultimately want to do with the truck, so can't really make an informed decision and should be cautious or you're going to end up doing at least some of what you change all over again.
I don't know about the others, but I assumed you were not even driving it since it sounded like you were in mid-swap with an NV4500 and an Atlas. Apparently you're driving it though, as you just said you blew up the rear differential. Doing what I might ask? And is this still with a stock 302?
Maybe the 3.50's and 33's were just too mis-matched for your driving style? Or do you think there was something wrong inside the diff already that just finally let go?
And not long into this conversation you're still not sure what you want to do with the rig, but are thinking of dropping in dual Dana 60's? Man, you've got a lot going on!
At least at one level, if your current use is putting enough stress on things to bust up a 9" diff, then a Dana 60 swap is actually making some sense for both ends.
After spending some time on it, it appears I can go pretty tall. 5.86:1 is looking like the right fit.
The right fit for what though? The 35" tires you've got, or something bigger? And what kind of driving? We still don't know what you will spend most of your time doing.
With 35's, that's a good off-road gear, but leaves a lot to be desired on the highway. How much time do you think you'll spend out on the road? That combo will put your engine at approx. 2500rpm at 60mph and 2900 at 70.
That's actually pretty good for power and crawling, especially with a 302, but is a bit high if you prefer lower rpm running.
With the 38" tires you should drop approx. 200rpm from that.
So that's your target. Which side of that do you want to run? Do you know what rpm range your next engine will be happy at? You going to make it carbureted or EFIed
Having my rear diff blow up in the last couple days is also forcing my hand here.
You've totally got us curious! What happened?
But you're right, it is a serendipitous occurence for someone that was contemplating gear changes.
If I was to go in the direction of an ATK 302 and wanted to consider Dana 60 front and rear which products should I be looking at?
Not up on my current Dana 60 lore, But Dynatrac, Currie, and probably a few others, including Dana themselves in fact, will make you a very wicked combination.
Maybe I should stop hanging out with hot rod guys.
Maybe! But it sounds like they're your crowd too. Maybe mostly still? Or at least have been hanging around them longer.
Are you hot-rodding your Bronco?
Maybe it's not that you have to stop hanging with one or the other group (even though I know that statement was probably facetious) but that you are going to need to interpret what you hear from each group and, taking it all into account and mulling it over, make your own decision based on what you like.
What about lockers? I work with a former Eaton guy who has been recommending their e-locker daily.
Love the e-Locker, but don't really have any experience with them. ARB is even more proven than Eaton when it comes to selectable lockers (just longer making them) but I'd trust either one.
Frankly though, if I had the choice it would be the Eaton all the way just from a plumbing aspect.
With the e-Locker you have a switch and some wires. Period.
With the ARB you have the switches, the valves, the compressor, the tubing all to keep safe too. I just think wires are simpler.
Yes, there are others. And given the choice I prefer a set-it-and-forget-it style like the Eaton Trutrac that was mentioned already. But my wants and needs don't include many of the things you're already going. So maybe a selectable is the best way. Detroit Lockers would be suitable, but are not my favorite and can still break like just about anything else.
You're obviously putting the fun-money into this rig so that it will be able to do just about any fun thing you choose to do. But are you really going to go rock crawling with it? Sand dune jumping? Mall crawling and cars-n-coffee showing with bragging rights? Heck, even drag racing?!;D
I still think you should narrow down your expectations and desires to the most desirable. Unless you really do want to do it all. In which case you are on the right track already.
That includes lower gearing than you normally need, because it makes it easier with big tires to go crawling and accelerating from a stop. Heavier duty axles and diffs because of the big tires and powerful engine. Bigger engine because of all the added weight and rolling you're adding.
Which brings me to the next question. Do you really want a 302? Even a built one? Or should you be contemplating a stroked 351 derivative at this point?
You won't "need" it for 35's of course, but if your honest assessment of your desire has you going bigger next time, you would do well to think of a bigger engine for more torque at lower rpms.
And more ability to break the next thing!

It's that big rabbit hole leering up at you.%)
Good luck with the repelling gear!;D
Paul