I have a couple of questions for you. Does the FM2-A insert convert the tuner to a stereo or is it just an amp?
The second question is how hard are the inserts to find? I have a chance to buy a mono tuner that was stored for many years and is in almost new condition. It not even dusty inside. I am thinking of it for a restoration if it becomes a stereo tuner with the insert.
BTW your new amp schematic is a very elegant and simple design design. I admire your work on that one.