It was as I hoped, just a little difficult but not at all complicated! I started with just the 6 chassis screws rather than every single one like in the first post in the thread. The boards slid right out. I went slowly so I could make sure nothing was ripping out and saw the two slip fit ribbon cables that connect the front panel (display, volume knob) to the logic board. Gently pull them out with your fingers or thin pliers. At first I thought I fucked up not remembering the orientation but the back side is blue so that was fine. Once they're out you can slide out the entirety of the guts. The PSU is on a daughter board. Disconnect the AC block connector from the front, the positive/negative spades on the back, and then the 4 screws that hold the PSU to the daughter board. Swap in the new PSU and redo everything you undid. The PCBs have rails in the case to slot into and since it was just me I put the case down and dropped the amp in. See the problem with this? Gravity took the ribbons all the way back in! Did it again with threading the ribbons and dropping the case down on to the amp. Get it about half way then reconnect the ribbons. I'm a big guy with big hands so while I could do the narrower ribbon with my fingers I ended up using thin pliers for the wider one due to the location and surrounding components. Powered it on with just AC to make sure I wasn't going to blow up my speakers, everything looked good. Hooked everything else back up, tried
@Toku 's test track, no more clicking! The power on click is still there but that has never bothered me.
I'd say all in all it took me 20 minutes, but I was being very slow and deliberate. The ribbons were the only part that made it even a little difficult. If they had been at the back of the logic board instead of the middle I'd call it a super easy project.