Ron Paul contested for unbound delegates in that example. Irrelevant to the question I asked.
Cruz is going into state delegate selection meetings and attempting to have unfaithful, or double agent delegates assigned to the winner (Trump), individuals who will actually be loyal to Cruz, the loser of the state's primary vote. Cruz is trying to have disloyal bound delegates assigned to Trump.
I conclude that you cannot supply any examples of where that has been done previously.