Doug,
Sadly, both Byars brothers have passed away. The brothers were partners in Precision ProFormance. Bob sold parts and Don worked on cars, mostly doing restorations. Both had worked for Hall Pantera at some point and Don even worked for Steve Wilkinson for a while. Don left the partnership and opened Full Throttle Panteras as he needed more space. Their separation was completely amicable and they were each other's best customers. Prior to Don's passing a couple of years ago, he sold Full Throttle Panteras to Greg, who had been Steve Wilkinson's mechanic for a long time. I hear the work is still great and the prices reasonable. I'm sure Greg also knows the sources for most of the parts Bob and Don sold.