Simple dynamic component, am I going about this correctly?

Im trying to make a simple dynamic component that is basically a rectangular slab with two rounded corners. This will need to be sized/scaled along the x and the y, z will be a fixed length. Thats all pretty simple but what Im shooting for is the two radius corners to remain the exact radius regardless of the scaling. Am I correct in assuming a way to go about this is what I have shown in the screen capture? The two radius sub components are fixed in all dimensions, the center filler that spans between the radius components scales within tied to the main slab (rectangle)? Then I just have to figure out how to anchor the corners to the rectangle as well as the filler to midpoint of the slab?

Have only made a few forays into dynamic so its slow going but have gone through all the skill builders and a few others trying to get my head around it.

Looks correct to me. The little radius components will then only need to be positioned appropriately relative to the parent component’s origin.

Thanks Dave,
Got it working, as a follow up, any tips/tricks to getting rid of these lines that show from hiding the lines/geometry between the components? Im likely not using the best style as my default. All I did with these was to create the components then once I had everything running properly for the dynamic went in and erase+shift to hide all the mating geometry.

These are probably the faces that bleed a bit.
You can erase them, or if the dimensions are ‘final’ create one solid with the solid tools.
If you keep the main component, it’s attributes will remain.

Thanks Mike,
These are parts that will have to be re-sized many many times (hence the dynamic component). I will hiding the internal faces as well as I only hid the lines.

You could do even better by deleting the meeting internal faces. Then there’s nothing to bleed through.