1. If you have a 2pin or 2wire connected to pcb
Get an untailed fan 80mm L1. Open up the power supply cut the red and black wires from both fans Strip the wire covering on the 4 wires connect red/red and black/black. To can use electrical tape, plastic wire connectors, solder+heatshrink, etc.
2. If you have a 3pin that connects to the ps(this is almost never the case) buy a tailed or buy an untailed then repeat the above and just cover up the yellow rpm wire.
3. 3pin connected outside of case(like the enermax) then buy a tailed + 6 inch 3pin extension and run it outside with the rest of the wires.
Assuming that your goal is to reduce noise, you'll need to remove the metal cutouts and use a chrome grill. Dremel is overkill and not should not be used because you won't be able to remove the bottom metal casing to protect against particles. Buy a small sheet metal cutter which is easy to use since there are ususally only 4 1/2" metal pieces connecting the cutout. Take your time and it should look something like
this when you're done.