The original dash gauge and sender worked in a range of 0-30 ohms. The modern senders work in a range from 30-90 ohms. The sender needs to match the gauge to make everything work right. It is usually easiest (cheaper) to make the sender match the gauge. The Runtz will make the original gauge work properly when the rest of the electrical system has been converted to 12 Volts. There you have it.....
Thanks Randy
