Best/Most cost effective option is to swap out the vac operated wastegate with the pressure operated wastegate. It's a hundred dollar fix and eliminates all the stuff in front of the battery. EDS then only controls the idle speed.
This is the thread.
http://www.peachparts.com/shopforum/diesel-discussion/212097-wastegate-actuator-swap-om602-962-a.html
It's very long, but well worth it.