Check out this Quality NAMZ by V-Twin, "Speedo-O-Wire Speedometer connector kit. This is used to modify 1996-1999 OEM harness to the newer type Deutsch connectors.
Wiring harness can be used with the newer 2000-2003 electronic speedometers as well.
More Information 32-0587
FITS Harley-Davidson  
FXST 1996-1998
FLST 1996-1998
UOM    1 - KIT
Manufacturer    Namz
Origin    USA
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Tech Note
Suggested to use with #39-0449 Replica Electric Speedometer.
Suggested to use with #39-0651 Electronic Speedometer Assembly.