The parties can run their primaries however they see fit.
So don't have a primary then. Don't have debates, don't pretend you care about your candidate. Put how ever many hats you need for candidates, lay them on the floor and asked them to be filled with donations. Whoever gets the most wins.
Invite Iran, Saudi Arabia, Canada, Australia, Norway, China, North Korea or any other nation to donate as well. Fill that hat up and pick the person who gets the most.
You just KNOW this is great for American interests...blue ribbon winners all their lives who would prefer to anoint rather than compete fairly. As I said in the OP, full blown Canadians.