The MVD will be housed in a thermal/electrical enclosure, which is mounted from one of the magnet nosecones. There is 5 mm clearance between the beampipe and the inner MVD surface, so there is a little room for global position adjustment. The beampipe in turn passes through a hole in the central magnet iron, with 20 mm clearance. Some of this 20 mm will be taken up be a heating system (for baking out the beampipe).
The mounting of the MVD on the nosecone will allow for small vertical adjustment.
One item that has come up is the effect of the thermal expansion of the
magnet iron. The distance of the magnet center from the hall floor
(approximately 5.35 m of iron) increases by 0.6 mm for every 
increase in iron temperature. Thus we either need to have dynamic adjustment
on the scale of 1-2 mm, or allow for a final re-positioning of the beam pipe
and the MVD after the magnet has reached a thermal equilibrium corresponding to
operating conditions. Alternatively, the movement of the magnet may be mapped
out years before the MVD arrives, giving enough confidence to mount the MVD
without the need for last-minute adjustment.