I run a crane cams hi-6 cd ignition and coil on my 360 mag in my truck, it has a wire to hook up a tach but I haven't used it yet because I need to finish making my gauge cluster on the dash. I have an aftermarket rpm gauge, I believe it's a sunpro.
Am I going to have issues with my tach and this ignition? I've read and heard stories about tachs not wanting to work with these cd ignitions, I have a tach adapter and I'm just curious if I am most likely going to have to wire this up or not.
Is there people here using the an aftermarket tach on a crane or msd box without any issues?

I've used the Crane hi-6 and aftermarket tach with no problems. Some tachs have both "hi" and "low" level inputs, try both to see which inputs gives the most stable (not bouncy) readout.