Well, it's been a fun adventure with this LS swap but the 6L LS fit and there was room to spare since the LS is narrower than the 4.6L. The motor mounts were easy to fab up and I picked up a set of Hooker short headers to clear the firewall on the passenger side. The wiring harness had to be ordered through Wiring Specialists and for now I'm running a HUD through my OBD2 plug so I have engine temp, speed, tac etc.
We used the factory X5 tranny mount and added 9" of bracket onto it to accommodate the shorter 4L80 tranny. We made an adaptor for the shifter linkage so the BMW automatic gear selector works fine aside from no sport shift.
We used an after market electric fan and thermostat for engine cooling.
We used the BMW rad and reservoir along with most of the coolant lines and power steering reservoir as well.
Once it was up and running and tuning was done, I decided to swap out the factory cam for an LS9 cam and delete the VVT which was also surprisingly simple. A little more tuning and it feels really good. Since the 4L80 only has 4 gears, in WOT, it shifts from 3rd to 4th at 170km/hr 'hypathically' of course.
Here's a short video of it idling.
https://youtu.be/lTnXZ1nZWKM
When just driving normal, it shifts smooth and works perfect. The amazing thing about getting it tuned, its done through HP Tuners so literally everything can be changed. We bumped the redline to 7000. It shifts in WOT at 6600rpm. The shift points were played with also so that under regular driving, its idling along in 4th gear most of the time and when you want to pass someone, i can either easy into it and it downshifts nice or I can hammer on it, and it jumps down 2 gears and takes off.
It is only rear wheel drive right now but with the factory 315 tires in the rear, it has tons of traction with plenty to spare.