Looking for a digital tach for my GTX S/C. Stock tach only goes to 8000rpm and my ski is reving well past that. Its got a RR computer and lots of other mods and I need to know what revs it is pulling.Somthing like a TinyTach would be ideal but they pick up of the spark plug leads so wont work with the coil pack set up our 4strokes have. Any ideas folks????