Finally had a break in the weather so I am going to get back to work on the X5. I haven't done anything since last post so thanks for the info.
The clicks sound like they are coming from the solenoid on top of the starter. When I turn key to start I hear 3 rapid clicks and the dash lights for cluster dim but come back as soon as I back off from start position.
I am pretty sure it is going to need a starter. But I will report back when I know more.

What is the consensus on the best way to replace the starter? Some say underneath with bunch of socket extensions to get around transmission. some say to come in from top. Remove throttle body, DISA, intake manifold and manifold plumbing.

I replaced mine from below. I took photos off the exact socket extension/flex joint combination. It wasn't a bad job. I did in the middle of winter i put a space heater under the jacked up car for a few hours in the unheated garage made everything relatively warm.

The best tip; remove the intake boot, disconnect the B+ terminal under the hood (no need to disconnect the battery), and disconnect the main alternator power it will give you slack to work with you can move the starter a bit to far far far easier dis/connect the power to the starter.

https://xoutpost.com/bmw-sav-forums/...ment-3-0i.html

Good thread for the job. I have a detailed write up including the extensions used.

Do you need to replace the oil filter housing gasket? CCV? Or replace the two coolant pipes under the intake? Fixing these issues will give super easy access to the starter. I updated these parts on mine. Seeing the starter so easy to access, I replaced it. The OEM one was still running. Apparently, cleaning the OEM one will make it last years. The replacement BOSCH spins up the 3.0 fast. If you are interested in refurbishing an OEM one to have ready to install, send me a PM.

Post of intake removal and starter replacement.

If the solenoid is clicking and the lights are dimming you most likely have a bad connection. Still a small chance that it's the starter but check all connections and grounds first. If you can get a voltmeter on the starter or engine ground and the firewall terminal while trying to start would be a good place to start. Do a search for "voltage drop test."

The no crank, no start, 3 clicks, power to all lights, and dimming lights when key is in start position ended up being a bad ground strap connection. I was in the process of swaping out the AC compressor last fall and something came up where I needed the car so I disconnected the AC belt pully etc. And ran the X with out the AC compressor. In doing this I did not properly secure the ground strap on the engine side. With the compressor removed and rushing I secured the ground strap to the compressor stud with the original long compressor bolt so it never bottomed out to engine block. I am lucky it quit so close to home because the day before I was 200+ miles away from home in NYC picking up my girls parents from JFK Airport. It goes without saying what a disaster that could have been.
I plugged the AC lines to prevent too much atmosphere getting in the system. But I am sure I will have some AC issues in the near future after I install the new compressor and hook everything back up. Probably not good for AC system to run the vehicle with AC lines disconnected for 6 months. Strange thing is I put my Launch x431v on it and did not see any AC codes with compressor removed.

Thanks for all the support. Always a good learning experience. You guys are Great!

That's why some history really helps too! ;) Make sure you replace the desiccant and use a good vacuum pump to evacuate the A/C.
If the compressor piled up then you will need flush the system and better off replacing the condenser. Not really a DIY job if you have no experience/tools.