I'm guessing that means the 6060 doesn't have a speed sensor? I waffled on buying one of those way back when when I swapped the T56 into my car since the T56 had a sensor. The main problem I had was that I wanted to keep the stock speedo and $300+ for one of those boxes just seemed like way too much to me. I'm a tinkerer by nature, so I figured I could build one myself way cheaper. It only took me probably 5+ years and maybe 7 different designs, but I finally got one that is working well that I'm happy enough with and was pretty cheap. It's basically just a tiny motor, an encoder, and a motor controller. I run it off the Raspberry Pi I have in the car that I use like an infotainment system, but you could run it off of a new Pi Pico just as easily if that's all you needed it for. Pretty much right at $100 all told. Motor is ~$25, $8 for the encoder, controller is $60, and a Pi Pico is $4. I think it was another couple of bucks for a cable between them. The motor is small enough it plugs right into the back of the speedo with a 3d printed mount I made. I feed my speed signals to my Megasquirt though and use an output from it to signal the Raspberry. I originally had the Pi reading the signal directly from the sensor before I upgraded my Megasquirt though. All that said, a nice clean box like that is certainly a good solution. I probably spent enough over the years trying to make things work that I could have just bought one to begin with and been done with it.