My NVX died

OK so I replaced the power supply with a Seasonic Flex ATX one. That was hard work but not too bad. I modified the cables going to the power adapter accordingly and all is well with the unit. I also had to cut the cables that were originally meant for the SATA drives because there was no way I could fit them in the case. I duct taped the ends to avoid any short circuits. The problem is that this power supply has a fan that although it was meant to be silent, it actually spins quite fast and makes noise, probably because the power supply's temperature goes up quite a bit. The ReadyNAS chassis does not have any grills where the fan is and the original power supply had the fan taken out. I am thinking of cutting an opening where the fan is to let the air flow or somehow disable the fan. The latter is not easy because the power supply cannot be opened easily. It might also not be a good idea in terms of overheating. What do you reckon?