For your OEM TOURING wires, see the diagram I responded with in my earlier reply - those are taken directly from the Touring model schematic
Some of those colours you mention - Brown nor Grey nor Yellow nor Orange nor Black/Green nor Black/White are simply not on the schematic at all!
You might be confusing me by your use of the term 'tacho' .............
A Tacho is an RPM indicator
A Speedo is a Speed Indicator
In English a TACHO is NOT a generic term for instruments, ONLY for the RPM gauge.
My understanding from what you described is that you were relocating the original TOURING model SPEEDO (which is CANBUS) and adding a Tach (only) from an earlier bike
My post #10 was with that interpretation
And in order to do, you would need AS WELL AS the tacho itself, the EARLY/CLASSIC instrument sub-wiring harness (which goes to both speedo and tach instruments) and use that harness to mate into the TOURING harness - whose wires would all still be required for the TOURING SPEEDO!
At this point I am not quite clear whether you are really adding JUST the TACH - or trying to add the complete SPEEDO and TACH PAIR from the early bike?
With regard your question on the Orange Wire (which I do not know what you mean - there is no orange wire!)
But - When you say '0 gear' I think you might mean Neutral?
There is NO standalone neutral signal on a Touring Instrument panel - that information is included on the CANBUS data stream