Tailstock position recovery

[kkungfu]

Hi all
SL-60/3500 with MF-6 (16TB)
I've had one of my customers clear all his paramaters by accident trying to cancel the overtravel on boot up.
Ive managed to enter everything back in (NC an PC param) and set all the home positions again, so everything is working fine on that side, only thing now is the programable tow-along tailstock position.

Does anyone know how to set the actual position of the tailstock? At the moment, when I go into rapid and push the joint button, Z will only move to home position before the joint light becomes solid.
I asume it is one of PMC data param and have tried tracing it through the ladder to find which one, but is very time consuming.
I do recall years ago I had some trouble with doing the same thing and there was a procedure to set it a D param or keep relay or something.

Any help would be greatly appreciated.