Not my PC, but a family friend had their system die and needed it fixed.
It was originally an FX 8320 system with a Gigabyte motherboard (one or both of those components were dead). It had a 120mm Corsair AIO (not sure what model), the motherboard was "screwed in" with the wrong screws. It was kind of a mess.
I sent them a parts list with a 200GE, 8GB of DDR4-2666, and an ASRock B450 motherboard. They got the parts, and my dad and I assembled it. Used new screws, redid cable management, redid the fan setup.
I reused their old case, PSU, GPU and SSD.
I think it turned out pretty well. It runs very cool and quiet and the CPU stays below 50C under load.