Need ideas for engineering course

Two ideas come to mind:

First, use a series of markers to have the learners click and reveal the information you currently have called out by the lines and terms.

Second, if there are sections of the equipment that are logically (and functionally) connected, you could make the image into a series of shades - so that each section is outlined in a specific color, and when you click on that specific section, the other sections fade to gray or are shaded and become nonresponsive to the user mouse interactions. And then in the respective sections, you could create hotspots to click that would show whatever information you want about that section of the equipment.