Nice looking brackets Brian and Ron. My panels were too far away from the Yakima tracks to be able to bolt them directly. That's why I used the square tubing. I thought about the Z bar but no one had any here in my town. I bought and installed the little spacers Bernard recommended. Finally decided on just a lock washer under the bolt head and locktite blue on the threads. I put a 1/4" spacer under the rear cross bar so that the nuts under the panel don't hit the roof if the 1" has too much deflection on rough roads and so that my MC-4 branch connectors will fit underneath. My front cross bar I was able to bolt to the existing post left from the old rack I removed. It's kind of like a safety chain on a trailer. The bolts can come loose from the tracks but this one never will. I still need to put a lock nut on it but then it should never come loose. It also keeps the front crossbar from bending.
It's amazing how many different ideas people come up with to mount solar panels to their roofs. This forum is amazing. Now it's time to head for the hills and see how everything holds up. Here's a couple of pics of my final install and attachments.