The second time I tried the damaged Install DVD in the new tray-loading drive, it refused to boot. Thanks to AppleCare, I'm receiving a replacement Install DVD with their complements. So far, I've been really pleased with Apple's customer service and that includes a lot of years.
Mac Pro dual Quad-Core Intel Xeons Early 2008; 16GB RAM; MacOS X 10.11.6, iOS 9.3.5
