Been playing with getting my "never worked before' 1928 "A" oval speed-o to actully read. It always just filled the oval hole and I read my speed by looking at my tach in high gear. But seemed to be time to fix that. So We have a 1928 oval "A" speedo that a I make a drive cable for out two cables,one "A" 1/2 an one 1957 Ford 1/2 to go to 57 ford tranny that hooks to { now a 65 Mustang rearend with 28in. tall tire=what could go wrong here?:eek:. I check out the speed-o and lub all,make my custom cable an hook it all up,first test is jacked up on stands and front all blocked,an let tires spin slow. Holly molly it reads some speed ;) So get my son to go for a ride with me ,he has GPS ground speed thing on his cell phone so we can check our real speed. We go to our local long block were we can run 40 mph on the dash for about 1/4 mile. Your not going to beleve what it read,as were holding 40 mph on dash,the GPS is reading 42mph :D WAy closer then I had hoped for really.