As long as you aren't using a cheap reservoir, the system should be watertight, but, if you do, I would recommend testing it by tilting with some paper towels near the top of the res. just to be safe. Make sure to clean the old TIM off the block before reinstalling it. As long as your tubing is flexible enough, you should be able to tuck it out of the way for the switch. If you are planning a loop right now and want to know about upgrade compatibility, get a Quick Disconnect port or 2 along the line so you can make changes.