Its very simple. There is a plug at the base of the oil filter/cooler contraption. The following two photos will help you locate it. I needed nothing more than what came in the Autometer kit, but I had a nightmare getting thru the grommet in the firewall near the master cylinder. Make sure to use liquid thread dope on the fitting and all should be golden.
1. Disconnect negative (-) battery cable.
2. Install sender ( included.) Sender fits 1/8" NPT and comes with 1/4" NPT
adapter. Oil pressure sender should automatically be grounded when
installed. If not, proper ground connections should be made.
3. Route 18-gauge wire through firewall using grommet. Connect one end
to terminal post on pressure sender, and opposite end to sender (S)
terminal on back of gauge. For 100 psi fuel pressure connect (S) to
sender terminal marked (S).
CAUTION: Be careful not to touch ignition wire to the sender (S)
terminal on back of gauge or the sender may be damaged.
4. Connect wire from center terminal GND (-) on back of gauge to good
engine ground. For 100 psi fuel pressure, connect sender terminal
marked GND (-) to good engine ground.
5. Connect wire from ignition switch to ignition (I) terminal on back of gauge.
6. Connect the lighting wires as shown in the illustration. The white wire
should be connected to the OEM dash control or a separate rheostat.
(See Note.) Connect black wire to good ground.
7. Reconnect negative (-) battery cable.