wiring diagram here.
Note that the wiring diagram is for the later car, but the
relevant wires are the same.
the siamesed large twin plugs, 28/53 (red) and 27/54 (blue), by pushing
out the pin between the halves:
- Connect the #53
red-wire plug with the #54 brown-wire plug
the #28 yellow-wire plug with the #53 yellow-wire plug.
27-brown are not used.
- Connect a jumper from either the
tachometer power (bat) or the + terminal of the fuel gauge to the
signal side of the voltmeter.
the alternator output is more than 80A, run an additional 8 gauge wire
(minimum) directly from the alternator to the battery or starter