Having tested this now. It works.
Obviously will not recommend this to run permanently.
The reason for the duct tape is because the L3 Boards are slightly too long and hang out stopping me from screwing the back fan on.
I also had to chop off the PCI-E Power Connector Locks.
Obviously using the D3 Chassis only 3 L3 Boards can fit. But this works and is mining Litecoin.
https://image.ibb.co/iN3v96/d3_l3_hybrid_1.jpghttps://image.ibb.co/gS5mGm/d3_l3_hybrid_2.jpgGreat job! then how about ur D3? you got so many D3 Cases for L3+? I dont understand why you got so many L3+ board without the cases , and also uses D3 cases and take out D3 hashing board . I think kind of waste