Where do I go in Osaka to convert my driving license?

I've done the research on documents I need and I'm ready to go and convert my UK license to a Japanese one. Where in Osaka do I go? I searched on Google and found a place in Kadoma-shi that's down as a 'driving test center' and I've found other schools but before I call around on lunch, I wondered if anyone's done this process before and knows where to go? I don't think it's done at the city office so maybe the police station?

Thank you