Initial height sensing for underwater cutting tourqe sensing

Hello what are some methods to make initial height sensing work for underwater cutting. I am using a hypertherm ht2000 with a pneumatic breakaway so I would like toavoid modifying it to floating head. Is it possible to accurately use tourqe sensing to determine the top of the plate when plasma cutting? 

Depends on what system is used on Z, steppers can not do torque sensing (even TMC drives miss that a lot), servos can do that but in most cases they would require opening the drive and soldering extra wires as not all have monitoring outputs.
The easiest way, floating head, and it does not miss.

Yes I am thinking the floating head will be the way to go I was thinking to build it spring loaded or with a adjustable pnumatic spring so that it could be adjusted to cancel out the weight of the torch.