I decided to drill the new Z brackets. Here is one that is setup for match drilling to the spar web. I used a square to make sure it was perpendicular with the spar.

I didn't want the crevice between the spar and skin to fill up with chips, so I taped up all the gaps. I wish I could find my blue painter's masking tape. I really don't want this regular tape to pull the primer off.

Update: FOUND THE BLUE TAPE! It had rolled under my wood rack. :-)

Using a modified version of the Checkoway method...I'm now ready to match drill through the baffle to the forward flange of the Z brackets. Got those drilled and deburred then knocked off for the night.