The "kit" linked in the OP is just the diodes and some lead wires soldered together. It will work on any bike. It's the section from the red to blue in my diagram. (There is a PnP kit using OEM plugs for the NewGen.)
The only thing I can think of is you wired the diodes backwards, which would cause the indicator to not work at all but should still stop the blinkers from bleeding over to the other side.
This really is a very simple thing (just made slightly confusing by the way the OEM setup is
*).
- Cut the green and gray wires going to the indicator.
- Add diodes to the green and gray wires coming from the bike. The stripe should be toward the indicator, not the bike. That would be the red wires in the OP's kit.
- Connect the striped end of the diodes together. This is the blue wire in the kit.
- Connect that to one of the indicator's wires (green in my diagram). That's now the + wire for the indicator.
- Connect the other indicator wire to ground. That's now the - wire for the indicator.
The junction allows either the green or gray wire to power the indicator. The diodes keep each side's power from being able to get to the other side via the junction.
*The stock setup uses the other side's blinkers to complete the indicator circuit. The inefficiency of the bulbs means the little bit of power coming through isn't enough to light them up. When you switch to LEDs, that little bit of power is enough for them to light up. It's always happening in the stock setup, but you can only see it with LEDs.