I don't know anyone in the Blythe area to refer you too. Maybe someone else will chime in? This is how I adjust my steering on my 96 RN,
1. With the steering cable installed, bolted in on both top and bottom, (there is no adjustment on the cable itself) and with the cable disconnected at both the top and bottom, I center the cables throw so its equal -can be pushed in or pulled out an equal distance. This should be where the cable should sit when you're going straight.
2. Then set both your bars and your turn nozzle as if you were going straight.
3. Then without moving the cable, adjust the brass fittings on the cable ends until they match the ball joint connections.
You're done. If this doesn't fix the problem then you very well may have a cable problem like OCD Solutions suggested. BTW, You need at least 3/8 of cable threaded into each of the brass fittings, you shouldn't have to adjust them very far to obtain this.