Just FYI, if the EcoBoost is the path you want to pursue, you WILL be paving your own way into a JK. I'm not saying it can't be done but you will be on your own to integrate the electronics especially. Motor mounts are not groundbreaking as they are merely fabrication but the electronics is where it gets tricky. That being said, I'm not as impressed with the EcoBoost as most people are, it's still a small engine.
I guess I'm still old fashioned in the way I look at things and torque is what it's all about for an off-road vehicle unlike horsepower which is what is needed at the track. The 3.5 EcoBoost is technically smaller than either the 3.8 or the 3.6 even though it does put out superior HP numbers. It does this through technology and forced induction which I think have their place but for off-roading and getting into the back-country I don't think there is a viable replacement yet for good old displacement. Even the little 5.3 I feel is a better option due to its torque numbers even though it is only about 1.5 liters larger. In a lighter JK this would equate to a big improvement. In a heavy JK it would still be an improvement but not has dramatic as the torque just isn't enough. Granted anything larger is going to be better than the V6's in the JK in my opinion but cruising up grades at freeway speed in a heavy JK with the 5.3 may not be as much of an upgrade as expected. Off-road I think the 5.3 would work equally as well as its larger brothers. The 5.3 is what I was first contemplating about 4+ years ago but after driving a few and wheeling a bit more when I started looking again early in 2018 I started looking more at the 6.0 than the 5.3 as my JK had gained a few pounds over the years. When it came time to start purchasing the powertrain I couldn't find a 6.0 that didn't already have well over 200k miles and I was looking for something with a little less even though the engines will go several hundred thousand. I stumbled across my L94 6.2 liter LS crate motor and search was over. I still think I would have been happy with the 6.0 but the 6.2 makes me smile every time I drive it.
If you really want to see some cool EcoBoost swaps, there is a guy over on garagejournal who has done several and the workmanship is top shelf all the way. Here is a link to his EcoBoost swap thread.
1966 F100 EcoBoost Engine Swap & 1966 427 Project I had a couple requests in another post to show my EcoBoost project so thought I would start another thread. I love the 65-66 Ford body style and have since my Dad pulled into the drive way back in October 1965 with a brand new Red/Red 1966...
www.garagejournal.com
Bottom line is I guess if you want something bad enough anything is possible.
Mike