Not hard at all.
It is not that hard. If you get the autometer tach then there should be instructions with it. If you plan on gettin an autometer call and order it from them. They have to recalibrate the tach to read the correct amount of pulses coming from the coil. When you get the tach there will be instructions and If you go to the website it will tell you where to hook the sender up to.
hope that helped.:thumbup: