How do I change locks?

Hello friends, I hope you've found answers to your problems or questions. Well, if anyone can answer mine, I'd really appreciate it... Look, I have a 1985 Nissan Z24 4x4 pickup. I haven't been able to find the manual, so I've decided to install manual locks. Mine currently has automatic locks. If anyone has already changed them or knows how to do it, I'll be waiting here. Thanks, take care