Double cardian front drive shaft and 4l60e is a no go. There is simply not enough space.
For your needs, a
@TRAIL TAILOR coil swap kit is probably what you are wanting. A 3 linked front will be way way way flexier offroad, but since you are planning on driving your family around with it on the street, i wouldnt go with a 3 link. Especially since you say you plan to take the bypasses on the rubicon. 3 link is generally what people do when they have maxed out what they can get from the 80 series radius arm setup while NOT taking any bypasses and need MORE flex and performance. Everything is going to be a push/pulll with suspension. If you push towards offroad capability, you are going to pull away from road driving manners and safety. Same for the other way, push towards all out perfect street driving manners/ pull from offroad capability.
The caveat on leaning towards street driving manners is the oem 80 suspension flexes way better than the 60 series setup. You can set up the 80 suspension and add thicker whiteline sway bars for the best road driving manners, then just add a way to disconnect the sway bars at the trail and gain a bunch of flex back. That way you eliminate body roll on the street but still flex better than before on the trail. I havent added the sway bars to mine because they are spendy but plan to. I still have the oem 80 series sway bars front and rear
If you go 3 link, youre going to need to install a much beefier swaybar (currie) for it to handle decent on the road. OEM sway bars wont cut it. Then youll need to be looking at much more expensive coil over options and shocks.
The Trail Tailor kit is just an 80 series setup so youll be getting much cheaper coil springs and shocks. Id say a 3 link will at least triple the project cost at minimum. Also there are no purpose made 3 link kits for the 60 series that iknow of so youll be starting from scratch, or trying to make an 80 series kit work for the 60. The TT kit is like 1-1.5 days of install fabrication work (including waiting for paint to dry) and not really that bad of a job up front. The rear is much more intensive.
As far as the cut and turn goes. You can do it, imo its technically the Correct thing to do, but i didnt. Cut and turn is to get your pinion angle to caster correct. As you increase caster you pinion points up. You need your pinion flange angle and your tcase output flange angle to be pretty much parallel. people with 80 series just swap to a DC front drive shaft and call it a day, but since you are going to use the 4l60e, there simply isnt going to be enough room with your trans oil pan.
When you are setting up your LS swap, be very mindful of the amount of rearward tilt you are setting your motor up with with the motor mounts and the trans crossmember. You only want 2* pointed down going front to rear of the truck. So on your front output flange of your tcase that will give you 2* pointing up. In an absolute perfect world you would want your front axle pinion angle to be pointed down 2* to match that but then your caster will be somewhere in the -3* range which is not good. This is kinda where the cut and turn comes into play. After you set your desired ride hight with your springs, you would set your caster up to be in the stock 3-4* positive and then cut and turn your knuckle balls to make your pinion match up with your tcase output flange. This is a ton of work
In reality, you just kind of have to get your caster as close as you can to the stock setting ( id aim for 3*). Your front pinion angle will be off some and it will vibrate at speeds over 30-40 but how often are you driving that fast in 4wd? Since you are adding manual hubs to the axle, youll probably only be using 4wd for slow speed stuff and you wont have too much vibration. I honestly dont notice any at all on mine and i have too much caster.
This is a long winded way of saying... just do the TT coil kit, set your caster, and dont overthink it. If you are ever near Portland Oregon, give me a shout and youre welcome to drive mine
