Click Orient in the Assembly group on the Design tab.The Align tool guide is enabled by default.
Uncheck Create conditions in the Assembly Options panel.
Select an edge or face of the object that you want to move.You can
Ctrl+click to select multiple objects.The Reference tool guide is
enabled.
Select an edge or face of the object that you want to remain
stationary.The components align. You can control the alignment animation
with the Animate Full PullAdvanced SpaceClaim option.