When building the Tamiya 54000 dampers for an M06, how many O-rings or mm of spacers do you put inside the shock under the piston to limit down travel? Also, how many on the outside to limit up travel?

I know you need to use the longer piston rod for the rears, but the different instructions (M06 pro vs. M06R vs. 54000) seem to vary on travel limiters...