I'm interested in the answer to this too as I'm a little bit behind you and will be there soon.
My thoughts at the moment are that, unless someone says it's a bad idea, I plan to match drill that hole as I want to be able to put a cleco there to help hold everything lined up while I drill for the doubler. You can't cleco any holes further out to hold it all straight as they foul the doubler (although mine's an RV-8 so might be slightly different).