I heard back from Zenith builder support today. For some reason my hinge hole is closer to the gusset bracket than it should be. I measured exactly 135mm from the center hinge bracket flange end, but I didn't verify the measurments of the gusset. According to Caleb the factory demo plane has 11mm from 7H5-3 to the edge of 7H5-4. So I'll trim about 10mm from the gusset and perhaps add a doubler to the gusset. Also according to Caleb, trimming the gusset is not an abnormal step to take to allow full motion.

It also turns out that you need to drill the holes for the cotter pins on the outboard hinge pins. I'll have to drill out the rivets ( getting those out of the elevator will be a pain! ) and then conscript a drill press to make a 1/16th" hole.