This is correct with regards to my 2 bikes that have more or less the exact same setup, but the rear mech hanger on the Marin is quite a bit longer than that on my Secteur. I bought another Deore rear mech for the Marin which is in the pictures on the previous page. But the top jockey wheel was miles away from the any of the sprockets with the B screw right out. So I looked closer and noticed that the rear mech hanger is quite a bit longer. So I have just been out in the garage and took the Tiagra rear mech that wouldn't work on the Secteur and put it on the Marin (as the one off the Marin is way older). It works perfectly with the B screw nearly all the way in. I am not sure that it would take a bigger rear sprocket than a 28t. So I have a brand new Deore rear mech surplus.
Tiagra rear mech big/big (52t chainring/28t cassette).
Tiagra rear mech small/small (28t chaninring/11t cassette)
Marin Mill Valley rear mech hanger (before B screw screwed nearly all the way in)
I did notice the rear gear cable that I somehow threaded through the mudguard stay on these pictures and rectified it
I would just like to say a big thanks for all the help I have had off forum members with these issues, very much appreciated. I have certainly learned quite a bit lately