Jenn-Air Wiring

I inherited the job of fixing an older Jenn-Air model S160 range that has numerous wiring problems–I found some exposed wiring and burned female contacts, which are all easy to fix, but it looks like someone rewired the burner element to be a 3-wire system, while the range wiring is all 4-wire (and some of it looks like it’s been changed). There is no wiring diagram, so I do not know the correct wiring for either the burner or the range inself. Help!