I posted a question on the forum a couple of years back when I was working on a gear position indicator for my daughter's GL1800 and was trying to find out if anyone had one working using the onboard gear position switch. My inquiry did not get any responses so I don't know if there is no interest or no knowledge. I purchased a 2010 GL1800 July of this year and have the design complete and working. Rather than going into a lot of boring details about the design if anyone is interested contact me and I will help you as much as I can. I'm 75 years old and not interested in getting rich and certainly not interested in teaching electronics. If you have the ability to make the digital part work then contact me and I will help you with the signal conditioning.