quest. about my new tach dash.

[BUXMAN66]

got me a new tach dash !! just need to figger out how the original (need to get one) style tach harness will hook up w/ my hei style of dizzy? will i need the harness or can i use a separate wire from the back of the tach (coil) to the hei, and use another wire from (12v) on back of tach, to a 12volt power source? or....does the 71-72 style tach harness have a plug for the hei style dist.? didn't they have hei on the 71-72 models...or was it still points ? thanks for any and all replies....