Update 1/23/21 Sorry I forgot to add the 3mm spacers that go under the Primary, Secondary, and Buck when mounting to the chassis.
I built this mainly to power my chargers for my lipos but can be handy for lots of things. the main 3 right side outputs come straight off the main 12V power supply at 850W - 70A, it has 2 USB's, in the middle the Buck power supply comes off of the power booster it can do 0V up 50V at 20A, on the left is a 1or 2 cell lithium Ion charger. I used the stock main power supply fans and added a third 40mm fan for the power booster.
I will not go into how to build the whole thing but it isn't too difficult and hopefully the pictures will help and most parts come with instructions, I am currently am working on a second one and will try to get more detailed with the pictures to help but I wouldn't try this if you are not comfortable with electronics, you will have to dissemble the main power supply and extend the wires from the primary to the secondary, solder the jumpers so the power turns…

Update 1/23/21 Sorry I forgot to add the 3mm spacers that go under the Primary, Secondary, and Buck when mounting to the chassis.
I built this mainly to power my chargers for my lipos but can be handy for lots of things. the main 3 right side outputs come straight off the main 12V power supply at 850W - 70A, it has 2 USB's, in the middle the Buck power supply comes off of the power booster it can do 0V up 50V at 20A, on the left is a 1or 2 cell lithium Ion charger. I used the stock main power supply fans and added a third 40mm fan for the power booster.
I will not go into how to build the whole thing but it isn't too difficult and hopefully the pictures will help and most parts come with instructions, I am currently am working on a second one and will try to get more detailed with the pictures to help but I wouldn't try this if you are not comfortable with electronics, you will have to dissemble the main power supply and extend the wires from the primary to the secondary, solder the jumpers so the power turns…