I am using hotspots on callouts for navigation. This works great most of the time, but I am having problems if the items called out are close to each other. Example - when you click callout 3A it takes you to 3D. Sometimes I can put the callout on the same part that is located further away, but when I can't it's creating a painful situation. My solution so far is to create a sub-section view (since it is not a natural assembly) that is zoomed in on. Generally more work and a pain.