Ignition wiring for a Suzuki GT185
 

I have a Suzuki Gt185 1978 I believe and it was my grandfathers and has been sitting in the corner of my garden for about 15 years. My grandfather is no longer alive so my grandmother gave this to me as a project however I came across that they didn’t have the key so I took the ignition off and have come across 4 different coloured wires a red and orange, a brown and a grey wire. I’m not sure what these wires mean and I want to replace the ignition however I’m not sure about the wires and what they translate to with later/newer ignitions.
https://cimg8.ibsrv.net/gimg/suzukif...0092b717d7.jpg
This is the ignition I took off of the bike and the wires don’t make sense to me and I can’t find a wiring diagram.
https://cimg9.ibsrv.net/gimg/suzukif...2061a3dca.jpeg
This is the Gt185 where I got the ignition from it is a 1978 I believe