Welcome to the forum!
Sorry . . . I don't have any specific feedback on your situation, but you might find a better audience in the following "Sprinter and B-van" forum:
https://www.airforums.com/forums/f240/
There are very knowledgeable Interstate folks over there, who will be able to point you in the right direction. If you see a relevant earlier thread listed there, you could "Quote" a particular post and ask for advice.
Hopefully they will also notice this thread in the list of recent discussions. If not, starting a new thread in that forum would be a good move IMO.
Good luck,
Peter
FYI
FWIW