There has been some discussion on it so I made up this little "how to" for others who may wish to do the same.
The parts are from Radio Shack. Their #273-059 12volt DC Piezo Buzzer sells for $3.50 and their #276-1101 is $1.00 for two diodes. The diodes are required as they keep the current flowing only in one direction and prevent one side from turning on the lamp of the other.

Step 1) Wire up the diodes as shown in the picture. Twist the two ends with the bands on them together and solder to the red lead of the buzzer. Solder about 10" of wire to the other ends of each of the diodes. Solder another 10" of wire to the black lead of the buzzer.
Tape or shrink-wrap all connections completely so they do not short to the steering column when you install it.

Step 2) Remove the front cover from the steering column of your Spree.
Underneath you will find the leads that attach to the front signal lights. They are orange, blue and green. The orange and blue are the positive wires to the signal lights and the green is the common ground or negative for both.

Step 3) You will need to use a razor to carefully cut away about 3/8" of insulation from each of these wires at the point where they go into the wiring harness. Solder one of the diode wires to to the orange lead and the other diode wire to the blue lead. Solder the remaining wire from the black side of the buzzer to the green lead.
Before taping everything up... test it. Turn on the key and rock the signal switch from left to right. The buzzer should chirp each time the lamp is lit for that side. If all is well, tape up your solder joints and stuff the wires back into place.

Step 4) You can mount the horn up inside the instrument panel with some double sided foam tape (from R.S. or Home Depot) as I did. That's all there is to it. The buzzer should be loud enough to hear over your engine but if it is not you can mount it on the cowling under the instrument panel so that it's facing you.
Drill a small hole there and cement the buzzer's opening just over it.




