IMO, it's just a bad idea.
I can only assume if you're renting your TC you're also renting your truck, correct?
I could be wrong, but I don't think there are very many insurance companies that would embrace that idea . . . but again, I could be all wrong. Certainly researching insurance possibilities needs to be your first step in the process.
Then, if you do follow-through with the idea, as others have stated, be ready for damage to both the truck and the TC, both seen and unseen. Nobody treats a rented vehicle like they treat their own.