Hi all, anyone know which wind back tool I require to change my rear pads on a Audi A3 2.0 TDI 2008, right or left handed?

Good question, sorry for late response but I think you'll need to wind them in a clockwise direction.

The trick is to clamp the hose and release the fluid in the caliper to allow the piston to retract with no pressure behind it. This practice also allows the old fluid to be expelled and also doesn't send the pressure up the system which can flip the seals in the master cylinder and also damage the ABS modulator. Safe practice and path of less resistance!