My TC was previously registered in Washington and had a plate.
No plates on the TCs in Montana. DMV said that’s what you have a front plate for. I have a (heart) Montana plate on the TC now. I figure they’ll notice that I put something there on purpose and didn’t just lose the plate.
I haven’t been everywhere, but I’ve been in Montana, Idaho, Oregon, Washington, and Wyoming that way. My guess is that a LEO that’s paying attention knows how to deal with the scenario. Since I don’t drive that fast with TC on, I’ve been passed by highway patrol as well as other officers in every state.