I think Trump thinks of himself as conservative but he doesn't understand what conservatives mean by the term.
I also think he is the only one who is firm on illegal and legal immigration.
And, before you question the one trick pony aspect, I have read two of his books and agree with him on taxes, healthcare, the military (including taking care of Vets) law and order, education, and other things I can't think of off the top of my head.