Do you still have the original EHC system in the bike? If you do you the run input to the EHC is looking for a ground to enable the ignition system. The easiest way to get accomplished what you want to do is remove the fuel tank. Find where the forward right hand harness connector meets the backbone harness connector. On the backbone harness side of the connector find the red wire. You can cut the red wire flush at the back side of that connector and using something as simple as an inline splice, splice some additional length to that wire. Then I would cover it with some heat shrink for protection and route it down under the coil cover.
Remove the coil cover and find where your key switch connector meets the backbone harness connector for the key switch. Remove some of the heat shrink on the backbone side of that connector to allow access to the orange and black wire. Take your new wire you routed down to that area and allowing room to add a splice, splice your new wire inline with your orange wire. I would at least cover that area with some electrical tape if not some new heat shrink.
Re-install the coil cover and the fuel tank and your good to go. Your ignition system run input is now activated only by your key switch being in the on position.
