4.27 gearing with 37" will work, but will likely feel sluggish during acceleration. Try it - if you don't like the performance, change the gear ratio later.
If you are looking to run 37", mostly for the look, you don't need Sasquatch (the locking differentials aren't necessary for highway operation). I would however suggest for the most efficient balance of speed and torque, moving to at least 4.7 gear ratio would be the best choice for 37".
I've got this on my Jeep - works great. It does however add 80+ lbs. to the spare tire carrier and requires a heavy duty bumper mounted swing mount. I doubt the oem Bronco spare tire carrier is beefy enough.
I think they will fit, but might look a little weird so close together. Maybe just remove the hoop and use the bolt holes for the Baja bracket? Are you going to add a winch?
I"m no expert on this, but I think the answers depend on what you plan to do with your Bronco. I've got a FE on order and I'm planning to see if a 2" spacer is enough to make the 37" fit w/o causing rubbing. The 4.7 will work fine with 37", but if you want the same torque specs throughout the...
See this Ordering Q&A - 10th bullet:
https://www.bronco6g.com/forum/threads/ordering-q-a-with-bronco-marketing-team-half-of-customers-will-get-my22.11701/
I'll probably just add the same after market accessories that I installed in my Jeep - wonder if there is a way to identify the switch so I don't accidentally launch a rocket.