Help with Rallye harness replacing standard harness 70 dart

If you have a rally dash (round gauges) and a rally harness, you should be really close. The harness to instrument cluster should match up.
There are other harnesses, like heater and ac that are separate harnesses in some cases. That may be confusing.

Year one only lists one under hood harness for a 70 dart, so that would seem to me to say the bulkhead should be the same for either style dash