Appreciate it fellas. To answer some of your questions the motor is very expensive if bought from mb new, $70k. Same as the tranny, $15k new from mb. BUT, I just picked up a complete motor, everything for $6500 with 21000 miles on it. I also picked up a used tranny for $1500, so there are alot of options out there.
Airmatic used to be an issue, around $1200 a corner, but Arnott has come out with replacements for $400 a corner. Lastly, KW is now offering coilover conversion kits for $2500. I personally love the airmatic as you can raise the car 2-3" at the touch of a button, it is nice and soft, great for dragging.
Let me know if you have any more questions, i love converting mustang guys into e55's. We have quite a few now on mbworld along with lightning owners.
$70k for a E55 motor???:shrug::shrug: A Nissan GTR and '13 Shelby GT500 motor isn't even near $70k and they have expensive plasma coated cylinder liners