I found a company in Pennsylvania that specializes in LED retrofits for signs. They manufacture the bulbs at their factory and send them out. I purchased 10 6' LED bulbs for about $45.00 each and two drivers for about $77.00 each. The bulbs were designed to snap into my existing sockets, but I had to remove my old ballasts, install two new LED drivers and re-wire the sockets to the new drivers. Took about three hours. I did it this summer, so time will tell on the longevity. Overall, I saved a lot compared to other options I found and the sales rep help design as needed. The company is Interlectric Corp. I was dealing with Dan Olson 800-722-2184 x144. I was a little skeptical until I talked to my electrical contractor here in Minneapolis and he said they have used this company for years. Hope this helps.