The connections are normally all done under the dash ... as all it does is holds the ING wire live till the time runs out.
The common connections are power from the "always live" wire a conection to the ING wire and an earth conection
This may help as well ...
copied from here
Hooking up the turbotimer is the same between the two diagrams:
1. red wire on turbotimer to white wire coming off of the ignition switch.
2. blue wire on turbotimer to yellow wire coming off of the ignition switch.
3. green wire on turbotimer to black/yellow wire coming off of the ignition switch.
4. black wire on turbotimer to chasis ground.
5. gray wire on turbotimer to pin 86 on the relay.
Now keep in mind, that you are not cutting the ignition wires and connecting them to the turbotimer wires, you are just running the turbotimer wires with the ignition wires. So just stripping a small portion of the ignition wires to expose them is necessary. You can either solder the turbotimer wires and the ignition wires together (recommended) or you can be lazy like me and just use wire tappers . Or you can be really really lazy and just wrap the wires together and electrical tape them
There is no mechanical problem so difficult that it cannot be solved by brute strength and ignorance.