Another option that might be easier and does not require taking the hinge off the flap:
- Mount the flap to the wing as discussed above.
- Use the now drilled hinge as a template to drill the holes in the 1/2” wide .032” aluminum strip.
- Machine countersink the holes in the hinge to accept the dimples in the flap brace.
- Use the non-dimpled and non-countersunk aluminum strip as a backing to the hinge rivets.
Here even though you countersink the hinge, you are adding a backing strip to the hinge to hold the rivet. So the hinge ends up sandwiched between the flap brace and your added aluminum strip. As you did not change the height of the hinge relative to the wing, you need not change the hinge attachment on the flap.