Third party is what the GOPe wants you to do.
The real answer is what the TEA Parties have been doing - work at taking over the GOP from the inside. It will take longer than the slightly less than 4 years they’ve been at it. This is obvious, if you think through it. You can’t do this overnight.
If we can't get Graham out of the Senate when the voters of SC can't stand the man, then we can't do what you hope.