Linking bounding box dimensions to properties

I have been creating bounding boxes on our sheet metal part by flattening and unflattening the part. Then I place reference dimensions on the bounding box lines. When I open the custom properties I click in my material description area and then click on the reference dimesions. This links the dimensions to the material call out. Is there a way to have the reference dimensions update automatically? Right now if I change something I have to remember to flatten and unflatten the part to update the link.