How safely can I replace the PCB on a HDD assuming I have the exact same board? Of course the data recovery websites talk about never doing such a thing yourself and let the experts(tm) do it for you at a nice low price.
One website selling the boards mentions taking the existing bios chip onto the donor board, but I'm assuming I'd have to do some soldering and not only do I not have the equipment, I have never soldered in my life. Which makes me wonder what would happen if I didn't do that. I don't recall there ever being updates to the firmware. I guess the donor could be from another generation.