Cardboard routing template for all Kahler bass tremolos. You will notice two creased folds in the template. The upper crease is for the models with forward facing saddles, where the crease marks the spot where your scale length starts. The lower crease is for models with the rearward facing saddles.
You can also use it for the 5, 6, 7 and 8 string bass tremolos if you cut it in half and extend the lines.