rvpiano,
Likely just the one fuse one the power supply board close to the IEC socket. Probably going to be a small size, slow blow fuse. If you pull the fuse the size will be stamped on the cap of the fuse and I’d guess something around 2.5 amp. If you go with Synergistic Research go one value size up. Chris at VH Audio can probably help on fuse size if needed. If you haven’t popped the lid you should to inspect. The IEC socket it what the power cord plugs into if you’re unsure. To be safe, unplug the cord before removing the cover. Once you locate the fuse by the IEC socket, check for others but I’d be surprised if there is more than two and I’m guessing just the one on the power supply. It’s should be very simple to change.