You may not need the voltage reducer. I'd remove it, re-connect the gauge and see what happens. Second, do you have a handheld electrical tester? If so, you can check the ohm reading of your sending unit (which depending on what you bought could have already gone bad...there is one good sender unit out there and about a zillion crummy ones). Here is how to do that: remove the seat back to reveal the top of the gas tank, disconnect the wire in the center (that's the one that feeds resistance to your fuel gauge). Removing the wire ought to cause your gauge to go full. Connect it to a known good ground and that should cause your gauge to go to empty. Check the resistance between the post where the wire you removed connects and ground. It should be between 0 and 30 ohms. If it isn't, then something has gone wrong with it. Let's start there.
