Hello Robert:
Here is a post I put up in the past week or so regarding the top nuts:
http://www.peachparts.com/shopforum/showthread.php?threadid=53156
I believe the torque on the top nuts is 25 nm.
The single large nut on the botton I "believe" is 85 nm, not 100% sure, maybe 80% sure.
In addition to obviously removing the top 3 nuts and the single one at the bottom, you also need to remove the rear sway bar links and the 2 long bolts on each lower rear control arm. When reinstalling the rear control arms, the truck needs to be resting on it's wheels before tightening the bolts. I usually do the tightening of these bolts on an alignment rack, i imagine it could be done on the ground as well.
The MB rear shocks come with the spring as an assembly, so never had to r&r the springs from the shocks.
I just noticed you said; "In looking at the front shocks", I believe you meant to say rear. Never had to mess with a front shock on an ML, plus it has a front torsion bar spring, not a coil. Plus you mentioned taking interior panels out, so I believe you are talking about the rear shocks.
Gilly