How to scale models with built-in scale bars

I have a .3dm mesh with scale bars. I want to place two points on those scale bars (I figured that part out) and then tell Rhino 5 that those points are 10cm apart so it scales my entire model… how do I do this? Thank you! I am using Rhino5 for PC but I also have access to Rhino7 if it is easier.

Please post a Rhino file.

Hello - use the Scale command - select all objects that you want to scale, set your base point and reference points to the two points, type in ‘10cm’ and Enter.
Any luck?