So, I'm in the process of setting up a small homemade rack system (more like a shelving system) and I'm wondering about setting up the Flexwatt. I've watched quite a few videos and get the gist, but something I haven't seen is how/where to place the probe for the thermostat. In other words, do I need to sandwich it between the shelf and the heat tape or between the heat tape and the tub? I would assume I don't want the foil tape covering the probe...? I'm really not sure which way is most effective and after using the search feature, I couldn't find anything on the topic. Sorry if the question has been answered and my search was just sub-par. Thanks in advance!