1989 642B Wiring

[mikeymed8]

Hi, I recently purchased an '89 642B machine. I've been going through and doing maintenance. I was working on replacing a defective hour meter this evening. Behind the hour meter and ignition, I have an extra blue wire with a black stripe. I have the service manual, I'm assuming it's wire #28, which shows it landed on the ignition switch, I can't tell which terminal though. The diagram also shows the wire going into the cab harness, but the same wire is not indicated on the engine harness? The ignition switch has been replaced over the years. Any ideas will be appreciated. Thanks, Mike