I bought my Killer B a few years ago used and a part of the nut just above the "E" string was chipped off. The string still set in the groove fine and it played well without it so i didn't think much about it. However, now I would like to replace it. I have replaced nuts on different basses and guitars before, but I can't find what type of nut to get for the Killer B. Does anyone know where I can find out or where to buy one? It is a four string model. I normally use DR low rider nickels in 45-105. Do I need to be concerned with the size of the groove in the nut because of the size strings I use?