A positioning transponder should be mounted on a high and visible spot. On a typical Sodi kart, this is right in front of the steering wheel.
There are two options for mounting:
1. Between the two existing pieces of plastic of the nose.
There is a space between the plastic pieces of the nose. The pictures below show this setup.
2. Mounting it below the plastic
This is more work in advance, but it doesn't put any stress on the plastic. You need an extra piece of plastic. Mount the transponder on the plastic and then mount the plastic under the plastic nose of the kart. Make sure you put the transponder in the same orientation as indicated by the image below.
The yellow and purple wires don't need to be used. Don't cut them off, they might be useful in the future.
The red and black wires need to be connected to the power supply. The voltage should be between 5 and 15 volts.