I my car I run an 11 position rotary switch to adjust traction control,
I prefer the switch rather than just a potentiometer as I can see and feel the adjustments on the go.
I run the output to a AN Volt INPUT and run a 3d allocation table.
I did this as I had no idea what slip % to start with and could try a wider range of settings on the go.
After playing I now have it setup at 9% slip in mid position and a difference of 1% per click.
I find it works quite well.