Even if Pence tries that, it might not affect the impending criminal indictment in New York state.

I don't think the courts ever established whether the sort of "and anything else we haven't heard about" pardon Ford gave Nixon was legally binding--and I would enjoy seeing Rudy Giuliani--or a competent lawyer, if Trump notices that Giuliani isn't--trying to convince a New York judge that a pardon that came before a trial and conviction could be legally binding.