Here's how to replace the strumplate:

First, remove the screws holding the top and bottom portions of the QChord and unplug the circuit board cable that connects the top and bottom.   You will see how the ribbon wire from the strumplate plugs into another board - remove this cable from the board. 

Now, the old strumplate needs to be removed from the plastic shell of the QChord.  You can use a sharp knife-like tool to help pry a corner of the old strumplate.  There are several layers of Strumplate “ Stuff”.  It all has to come off.  There will be residue left on the plastic which can be cleaned with alcohol.  Once it is all cleaned, it is ready for the new strumplate.

It will be obvious as to how to install the new Strumplate - it just needs to be placed on evenly.
There is a very sticky surface beneath a plastic covering.
 After you peel off the plastic, thread the ribbon wire into the QChord opening.
 Now connect the new strumplate to the QChord.  Do your best to keep it even.
Now connect the ribbon wire to the circuit board.  Line up the flat wire, then push it into the circuit board connector. 
Finally, reconnect the QChord top and bottom sections and give it a try!

Good Luck,  Len            ​