So long story short I need to replace the airmatic and compressor. I'm thinking about going to springs. Any suggestions?

 

Here's the Strutmasters page for the E55 coilover kit:

http://www.strutmasters.com/suspensi.../e55/2006-e55/

Here's the Arnott page for same:

http://www.arnottindustries.com/part...27_gid941.html

Both companies have tutorials and installation manuals for these linked from these pages.

I'm not sure you need to pay the extra for the module that clears the codes. Others have said you can simply pull fuse 37 and that stops any error codes that the airmatic system might throw after it's disconnected.

Good luck!

ETA: I tried to post those links as plain text because this site truncates the links, and then they don't always work right.