A generator would look like this.
Good quality - good price standard harness (use with generator)

An alternator would look like this.
Good quality - good price standard harness (use with alternator)

Neither of the above are like the original (more expensive) cloth braided wiring harness.

Both of the above harnesses will work on a 6v or 12v system.

Also, the only extra wiring/circuits provided in the above harnesses are for signal lamps.

Alternators probably became standard equipment in the early 70s.

If you have a 6v system, obtain new battery cables and ground wires = 00 (2/0) gauge are best, but use no higher/thinner than 2 gauge cables. The braided ground straps (from the frame to the clutch housing) should also be the same heavy gauge.