This is a MOC combination of 2x sets 41757. It consists of 2183 pieces, of which 103 are extra pieces and 2080 come from the 2 official sets. It is placed on a 32×32 baseplate and maximizes the space and parts included in the sets. The whole level is raised by 1 brick high so it is essentially already in MILS, The roof top is removable like any modular building.
You may view and download the extra parts list here: