Sad to hear you couldn't finish tonight, If i was closer to you I would of given you a hand but I just live to far away. Your so close to finishing that it would be a shame to take it to a shop and have them charge you ($$$) for just adjustment of the rear when you did all the hard work.
I would call Ravspec if close to you as I know Mark has them on his black M.
This is one of the reason I tell everyone to go with D2 Racing coilovers, they are true coilovers. They have more adjustments (36 way) and are so much easier to install and more important faster to dail in ride height. I would say most all people that have installed a non-true coilover set up (like BC or Megan) by themself are driving around with the rear adjusted wrong.
I hate to push product on others but I always give my opinion without force, I always try to help as much as I can. I always reply to e-mails, PM's and phone calls as fast as I can too. I like to give facts and not

like some around here do.
And yes Megan Racing exhaust system is the best bang for the buck for our M's, hands down.
And yes you should buy hid kits local to you so that you have some kind of warranty and not have to wait for shipping it out and then wait for it to come back to you.
And yes you should 100% get your Uprev tune done with a Dyno.
And yes the K&N drop-in filter works better than a pop-charger intake that cost +$300
And yes you should replace the same spark plug that your M came with, nothing else.
I can go on and on about what works or how it should work but I hate to see people like Ilyakol have such a hard time because of the product thats not 100% explained or product thats over rated which so many are.
I really hope you have a good night sleep and wake up ready to give it another go at it, never give up when your so close.
As for your lift try 2x4's under your 4 tires when trying to remove the lift arms then you just roll off the 2x4's