How to maintain arc tangency when adjusting object dimensions?

Hey, new to this forum. I’m hoping someone might have a solution for a specific function that seems to be lacking in sketchup. What I want to know is if there is a way to setup a component so that and arc which is tangent to a line will always remain tangent regardless of other dimension changes?

I attached a model here of a specific part which I would like to do this on. Hopefully this makes this a bit more clear. But basically I have a shape which consists of several straight lines and one arc which is tangent to one of the straight lines. I want to be able to adjust the length of each of the straight line segments individually and have the arc remain tangent as it grows or shrinks.
Does anyone know if this is at all possible to do?

Side Panel Test.skp (54.9 KB)