Ok just to close the loop on this one...
I went ahead and did the mod. I clipped one terminal of the diode and inserted a simple on/off switch at the break point. To be clear: I soldered one lead onto the clipped diode terminal (black wire in the center of the first pic), and soldered the other lead onto the back of the PCB where the lead had been connected. This way, I can effectively toggle the diode in and out of the circuit whenever. Then I drilled a hole in the back of the amp to house the toggle. Attaching pics for reference. Also, apologies for the crappy soldering job - it's not my forte.
The difference in sound is exactly like the youtubes. Removing the diode gets rid of the fizzy distortion at low volumes, and gives an overall fuller sound. But the difference is certainly not drastic.
@18allthaway - I'd say go for it. It was pretty simple. Let me know if you have any questions.