Is that a Thermaltake system....?? Since LCS stands for Liquid Cooling System..... what's the make and model of the unit?
Anyways, usually if the reservoir is mounted into the front 5.25" Bays, then on top of the case there is a Hole thru which you are supposed to be refilling the unit.
Cooler Master has a rubber sheet covering this hole and Thermaltake has a fiber panel slider on the top where you have the usb connectors
Check this video, it might help....