I have a 86 FLHTC, the oil pressure gauge was broken, so I went to the dealer for a replacement, but they are dicontinued. The factory replacement is a 99 gauge. It looks identical, fits perfectly and the connections are the same. I installed it and it runs backwards. With the ignition on, motor not running, the needle is pegged at 60psi, when you start it it idles at 50psi and when you rev the motor it drops to 30psi, exactly backwards. I reversed the connections and no change. I replaced the sending unit, which is still available, and still no change. Any ideas?