Below are the directions we are following. I got them from GoBabyGo - Riley : 8 Steps - Instructables
"For ease of use, we removed the pedal in the floorboard which moved the car, and added a Big Red Button.
However, this complicates things, as we don’t want the full power going across the Big Red Button, so we’re going to use a Relay. We chose the SARL- 112DF, with the wiring diagram pictured.
To power the coil of the relay, we’re going to tap into the battery power and run it through the big button to power the relay, and then from the relay to the battery ground. To simplify things, we’ll use the hot wire coming off of the emergency stop switch we installed earlier.
To activate the car, we’ll just use the wires from the pedal we removed to actually start the car. You can see from the picture that the pedal was just a simple switch that connected two leads. These leads are what we’re going to run across the N/O and common connectors. Make sure that 1) you use the normally open connection on the relay, and 2) you connect the “hot” wire to the lead marked 87 (not 87a).
You can identify the hot wire by turning on the car, and reading the voltage between each wire and ground. The one that shows 12V is the hot wire. (above, the brown wire with the electrical tape is the hot wire from the pedal; the brown wire without the electrical tape is the not-hot wire from the pedal)
We opted to use quick disconnects on the wires going to the steering wheel so that we could run them easily through the chassis, but it’s not required.
We installed the relay itself underneath the seat, with the other electronics and battery. Since the relay had a mounting hole on one side, we drilled a small hole in the side wall of the car’s chassis, and connected it with a bolt and nut."
