If you have a 4l80 in your tahoe then it will just bolt on the back of the trans with no issue. The shafts may or may not depending on the size u joints you have now, 1350 or 1310's.
Why swap out your 241?
I will check my speedometer to see to be sure. I will check the switch connector as well. Friday I tried 4lo just to check it before I went wheeling saturday and thats when It started. It wouldn't shift out of 1st gear while in 4lo. After shifting it in and out a few times it started working but...
It has also been shifting slower lately. It slides into gear very smooth but it takes longer to do it. I have Heaths Tune in it, about 1 year old tune.
Like I said in 4lo the trans does not want to shift out of 1st gear, then once wound up it shifts hard. 2nd is all it will do no 3rd. I have not used 4 lo for a long time, no need so who knows how long it's been doing this.
I would do the A team turbo, exhaust, change all the fluids, give the whole truck a good inspection and hit the road.
There is no reason you have to do any of the mods, I'm sure your truck will make it there just like it is.
I think Jamie covered most of everything. I like the ORU kit vs the ORD kit myself but it's just personal opinion.
Leafs springs for the front are standard 73-87 GM truck springs unless you use the ORU long leaf kit then you need a custom set of leafs, I used custom springs from Atlas.
Steering...
For what your doing, a warn 9500 would be fine. Your not 4 wheeling where the truck would be sitting in 2-3ft of mud. A snatch block doubles the capacity of the winch if you need it. Use a front hitch mount so you can use it in the back if needed.
On the over seas right hand drive trucks they use the center mount turbo setup like the vans do so it may all fit in there.
If your pulling the motor anyways see if the center mount turbo engine will drop in there.
What is lost when you run a strait centerlink? Does GM do that for packaging? My 06 van runs the same setup and even that has had 2 idler arms and 1 pitman arm withing 100k miles.