M1/3A1 Front Wall.
(2) Refer to figure 1-26.
On the vehicle adapter assembly, push the
locking handle (3) ccw to release the lock.
With one hand on the locking handle
and the other hand on the adapter assembly, move the adapter assembly up and down
and sideways until the bubble (2) inside the precision level (1) is roughly
centered within the ring.
Push the locking handle cw until the vehicle adapter
assembly is locked in place.