The Command Link works on HPDI and 4 stroke models in 1999 they used magneto system then in 2000 they switched over to Generator and coil/pulser; My honda works on 12V .key on the hour meter runs leave the key on without running the motor it clocks up the hours.

Knowing a little about the background of the question would help.
On most, maybe all, if you leave the ign key on, the hr meter keeps on turning over.
 I have around 150/200hrs on my meter over and above use.
 The grandchildren where playing in the boat , turned the key on.
 With most electronic type igns if left on the circuit disconnects the coils part.. unlike early car electronic car igns pre 80s.

 And maybe of help readouts history.
I contacted the service centre where the previous owner got stuff done. I think them being authorised dealers, they keep records of each engine for many yrs. Anyway they where able to email me all the engine records and service records for the boat for the last 2 owners.
If you chat to your local service centre they should be able to obtain similar records or get info off the engine.

I think a few guys fit these on their motors might look at one for my little 15hp