This is what I have learned. I will add pics soon.
My 06 M35 Sport was pre-wired for the reclining seats. I did a dry run and removed the bench seats and the reclining seat frames lined up perfectly with the existing bolt(s) and bolt holes in the frame. If you have noticed the black round stickers in various locations underneath the seats those are the bolt holes for the reclining seat.
The harness which extends from left to right about halfway up the rear fire wall (only term I can use to describe it) had, in the case of my car, several vacant/unused harness plugs and the reclining seat frames plugged right in. The rear center console with all of the gadget switches plugged right in as well. What is nice about the setup, as most of you know, you can't go wrong as the male and female ends are unique so there's no chance of plugging the wrong plug ends in. The large gray vacant plug is the AV system plug. Once I turned the car to the ACC position the AV portion of the center rear console lit up. I had the ability to control the radio system from the rear so I know that works. I couldn't operate the seats because the junkyard failed to send the two control modules with the seats (see below). I have them now and will do it on Monday.
REAR SUNSHADE: Since I was in so deep I purchased a rear sunshade from the same junkyard. It looks like my car is pre-wired for that as well. I will explain: As you know if you have seen a M with the recline option there is a "kill switch" in the front center console. Essentially the whole panel which, on most M's, has the ac/heat switch, and a small cup, of sorts, isn't the same. M's with the reclining rear seats have an option to disable, I think, the rear seats (for kids (or adults

that like to play with the seats it seems). Vehicles with the rear sunshade have a switch to open or close it as well and on some models the switch for the transmission (snow) is found there as well (a total of 5 switches with the a/c / heat). I purchased the entire panel from the junkyard as well. I popped the cup holder out to see if there were some vacant plugs to attach the new gizmo panel. What do you know, 3 vacant plugs! They plugged right in! There is a vacant plug in the trunk near the upper courtesy light and I am 99% sure it will plug right in (I will check on Monday) to the rear sunshade. Note: If you attempt this please, please, please get the rear control switch for the rear reclining seats located in the front center console from the junkyard you purchase the seats from. For some strange reason this switch, 28260-EH160, is $300! All of the other switches are around $25. Please purchase the rear deck from the same location as you purchase the sunshade as you will need that as well along with the flap.
Additional notes. There are two control modules, white box-like structures, 3x5x3/4 inch, which are attached to the back of each reclining seat. Make sure to get the junkyard to keep those units attached to the seats. They, 28565-Eh120, are around $500 each. You will need additional bolts (10 or so) to attach the reclining seat frames, 88999-EG000.
Rear DVD: I purchased the stock rear screen some time ago and it appears this is the only thing that will cause me issues. I will keep posted as to how or if I attempt to mount it.
On Monday I will take pictures of the process and try to share as much as possible. I hope all of this information helps!