Another Walker Mower Start Thread

Ok so I have a 1999 Model Walker Mower 20hp Kolher that I'm working on for someone. The problem is that it won't start with the key, but it'll start when i jump the starter.
I've read previous thread about this but I'm having problems locating certain things.
I'm pretty sure its a safety switch, I've read i can just unplug the safety switch relay that controls them all, but where is it? Pictures Below....
Any Advice would be great! Thanks!