E5. 9... , Also try Ken Jones, at Diesel performance of Utah... He sells a lot of Dipricol gauges, and can probally help you. I have Dipricol gauges also, and with every up-grade, the manufacturer changes the darn type of bulbs and sockets! If worst comes to worst, I'm sure Ken can get you a new set of sockets and bulbs that will work for your gauge. He can be reached at 801-791-2328, M-F, 9:00am-3:00pm Rocky Mountain time.
Steve