Ability to change vehicle build order/priority

Currently, as far as I can tell, if you are building a mix of vehicles, let's say an excavator and two trucks and you decide you want one of the trucks first, you'd have to delete the excavator, delete the second truck, then re-add the excavator and then re-add the second truck. That's not too bad by itself, but if you are upgrading existing vehicles it's very annoying to have to track them all down again to re-upgrade.
Please either let us drag and drop the items in the build queue, or add +/- buttons to move their build order around. It shouldn't need to be done too often so the specific method doesn't really matter to me, just the ability to do it at all without starting from scratch.
If it would be difficult to move the build priority of the vehicle currently under construction, it's OK if I can just move around the future ones that haven't started yet.

I was thinking the same exact thing yesterday, this would definitely be a great COL improvement.