Found this thing corroded, dirty, and dented. 30V/5A. Don't have a whole lot of experience with these things, but it's mostly working now. Voltage is spot on, current is touchy, waiting on a replacement switch. Main thing I know I'm still missing is a replacement center binding post. Needs to have a shaft ~26 mm long and 5 mm diameter.
Input voltage selector was corroded and had high resistance, so I just removed the switch components and hardwired it for 120V. Also replaced the 20 AWG neutral wire with 16 AWG.
The bridge rectifier gets well over 100 °C in normal operation, and got a lot hotter than that when the power supply was overdriven accidentally. Planning on replacing it with this:
https://www.digikey.com/en/products/detail/micro-commercial-co/GBJ5006L-BP/16718585I think I'll keep it mounted on the chassis, since the replacement should run much cooler. I also removed the paint from the chassis at that ground point on the bottom right. I didn't check, but I highly doubt the case was grounded previously.
This 4PD2 switch was causing some interesting problems. It is supposed to toggle between high and low current modes, the latter presumably reducing noise on the output. It was failing though, especially in the high position. This could cause the current reading on the display to be lower than it should be, sometimes just zero, but it would also increase the actual current well beyond what it should be - over 11A at one point before I shut it down. It has 4 mm pitch between pins, and 6 mm between the rows. This seems to be nearly an exact match:
https://www.digikey.com/en/products/detail/c-k/F4UEE/417520
There are a lot of oddities and unpopulated spaces on the board. My favorite is on the bottom left - the 3 hole spot for a potentiometer that is populated with a capacitor:
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