If the pic is your actual rig you already have two odd.  The motherboard can support up to 4 sata drives. Therefore you cannot have 4 hdd+ 2 dvd.  Dell does not have official cage to stack on top of riveted hdd cage but you can acquire a hdd cage and figure out a way to stack and fasten it on top of Dell stock cage. Downside of having 4 hdd this way: Air intake is impeded. There is a mesh of chassis front meant for air in take. You may need to drill some holes on side panel to provide air intake. two of 4 hdd will connect to white sata ports on motherboard which are lower speed sata 2.0 (while the black blue sata ports for hdd are sata 3.0) This may not matter much if you connect archive hdd to those ports and you do not care too much of access speed. If you have ssd connect it to sata 3.0 for max speed. you need to give up both dvd if you have 4 hdd. Alternative: use 2.5” hdd. You can stack 2x2.5” in place of one 3.5 hdd via adapter which can support two 2.5” on both sides of adapter and fit stock cage.  The limitation of up to 4 hdd etc. still present but you do not need a custom cage.
Hi community, I am looking to add more HDDs to my 7010 MT, and while there is room, I don't have actual cage for them to fit. I need to fit two or more standard HDDs. Is there some kind of official dell cage for this purpose that can be mounted in this spot (see picture). If not, what would be the alternative?   [IMAGE]  
HDD cage upgrade (Optiplex 7010 MT)?