The mod isn't all that difficult to talk through. The level of terminals on the headphone jack closest to the plate is the sleeve. You must make sure not to move those wires.
On the ring terminals, which are the middle level, the wire going to the binding posts goes towards the middle of the chassis, and the other wire from the output transformer goes on the outside of the chassis.
On the tip terminals, which are the top level, the wire going to the binding posts goes towards the middle of the chassis, and the other wire from the output transformer goes on the outside of the chassis.
The 120 Ohm resistors are removed
