I don't actually know which cooler you are trying to use. Nepton is a product name, not a model.
Either way, the only really supported configuration would be a rear mounted 120mm radiator. There is no practical way to utilize the top for more then fans, the space is just too narrow. You will hit the memory or CPU VRMs if you try to put radiator and fans up there.
Front panel can mount a 120mm radiator as well, but there is no room for the fan due to the fixed hard drive mounts. They are structural and can't be removed.
The side panel could be used, but that would be problematic for removal purposes.
I did look. It is a nice, cheap, simple case. Only change they've made to it in the last ten years or so is move the power supply to...