I pretty much feel the same way you do - I am a Conservative first, and a Republican second. There have been plenty of times that I've been so mad at the national party I could spit. I have no problem telling the Republican party to go pound sand should the circumstances warrant.
I did that. Every request for $$ goes into the trash unopened.
I won't vote for a RAT, but I won't give my $$ to a party that isn't truly conservative.
Withholding votes might work. Witholding $$ works faster.
Shalom.