Chris Hardwick posted a couple videos where he discusses setting up a very similar incubator, and he advises you to put the probe on the heat tape. He warns that, if you put the probe in the middle, the eggs closest to the tape will get too warm.
Links to his videos:https://www.youtube.com/watch?v=1SsGbkwP0cA, https://www.youtube.com/watch?v=3ZOeOFz7E0o.
I suggest you watch both. The first video describes the original set up. The second was posted a year later and includes info on adjustments that he had to make to the original set up. I don't have a personal opinion. I've never done it. Just throwing a contrary opinion from another breeder I respect out there for your consideration.