Alarm system installed but petrol pump not for radio start

Hello So I drive a Mitsubishi Lancer bj.97 1.3l Gl. I bought a 2 way alarm system and already installed works great. Only was there still a relay for the radio start with it. That must according to instructions between the plus cable that comes from the petrol pump Ralei, however I can not find this and also erlich not exactly where I could look. Under the rear seat is a cover under it I think the thing for the petrol display is sitting, in any case there is a stec It’s nice if someone could help me. Here’s another picture of the installation instructions.