Some things to think about from an experinced Canister filter user.......... Ive been using these things over my last 30 plus years in the hobby.... Some issues I see with your plan.
The INTAKE side of the filter opperates 100% off of gravity. Not suction not pumping pressure. But purely from gravity flow down the tube and into the filter. If you run it level you will have very very low to zero intake flow coming from the tank to keep the canister filled. While you will have less head pressure to run the pump on the outlet side, you wont be able to feed the pump due to the reduced to no flow.
Next..... Your putting this in a dresser and below its clothes you wear? Murphys law on canister filters. Isnt If it will leak. Its WHEN it will leak. There are 2 types of canister filter owners. Those that have had leaks and those that will. I see disaster and not so happy. The only good thing is your intake will be so poor it may not be able to leak a whole lot. BUT id bet its enough to ruin your day.
Next the amount of hose.. The length and the shape/position the hoses are in can and will effect flow rates. In the first pic you have I see the hoses are long and have some loops and curves. This slows flow and creates issues for air pockets when trying to prime. When in opperation the flow rate will go down. Most all manufactures recommend the shortest hoses you can get away with and recommend trimming them. They also recommend direct gravity flow. The pump in a canister filter is a pusher not a puller. So the effect of gravity flow also helps the water flow down to the bottom and up through all the trays and through the media where it reaches the pump in the head of the unit.
Purging at the same level as the tank will be more difficult.
Sun Sun pimp #72
RAOK CLUB # 68