Expert Wireman for Car Fuel Pump Relay

I am in the process of installing a relay on the main fuel pump wire in various car models. The challenge I'm facing is locating this wire at the rear door. Currently, I have a wire tracker to aid in this task.

Your Responsibilities:
• Identify the main fuel pump wire at the rear door using a wire tracker
• Install a relay on the identified wire

Ideal Skills and Experience:
• Extensive experience with automotive wiring and electrical systems
• Familiarity with varying car models and their wiring schemes
• Proficient with the use of wire trackers
• Adaptive and problem-solving abilities

While I do not have a strict deadline for this project, I'd like for the task to be completed in a systematic and thorough manner. No need to rush, attention to detail and quality of work are more important to me.

Please note that I haven't specified the car models, and hence, your experience across different models would be crucial.