Not really a question, but a remark. The measurement tool from Blender can be a little wonky to use in my opinion. I recently went through a project that required a lot more precision and found this free add-on on the extensions repository:
https://extensions.blender.org/add-ons/measureit/
Thought I'd drop it here in case anyone needs to be very precise too.. clearances and all that.
Disclaimer: the visuals can get a bit busy, but it's very easy to delete it all, or parts, and remeasure things as needed.
Great extension, integral part of my workflow.
Tip for the visuals: Make sure you toggle the little ghost icon next to the show/hide button. That way you'll only ever see the dimensions when the measured object is selected. Keeps the viewport much cleaner.