Best thing to do is use a schematic and wire in the three wires for the speed sensor to the correct pins on the ECU.

Ok Did the work for you but you need to verify the pin out on a 99. 97/98 are the same for the VSS signal pin at the ECU (pin 66).

Speedo needs 3 wires. When looking at the plug from the front side (back side is where the wires come out) and the clip on top. Numbers are from left to right
__^__
(1 2 3 )

Middle wire is location 2 and needs to be grounded. Run the wire into the harness and solder it to the middle wire of the Cam sensor (ground also).

Pin 1 is going to be a Yellow wire in the plug, this is 9v reference wire. Follow this to the spot where you soldered in the ground to the Cam sensor wire and splice into the yellow wire there as well. The Cam, Crank and Speed sensor all use the same 9v wire.

Pin 3 is the VSS signal wire to the ECU which is also 5v. This should go to pin 66 in A106 ECU plug (top plug in ECU).

Terry