Minecraft Model Stacking

{
    "default": { "model": "base_frame" },
    "variants": {
        "Top1=true":  { "model": "top_panel_1" },
        "Top2=true":  { "model": "top_panel_2" },
        "Top3=true":  { "model": "top_panel_3" },
        "Top4=true":  { "model": "top_panel_4" },
        "Top5=true":  { "model": "top_panel_5" },
        "Top6=true":  { "model": "top_panel_6" },
        "Top7=true":  { "model": "top_panel_7" },
        "Top8=true":  { "model": "top_panel_8" },
        "Top9=true":  { "model": "top_panel_9" },
        "Bottom1=true":  { "model": "bottom_panel_1" },
        "Bottom2=true":  { "model": "bottom_panel_2" },
        "Bottom3=true":  { "model": "bottom_panel_3" },
        "Bottom4=true":  { "model": "bottom_panel_4" },
        "Bottom5=true":  { "model": "bottom_panel_5" },
        "Bottom6=true":  { "model": "bottom_panel_6" },
        "Bottom7=true":  { "model": "bottom_panel_7" },
        "Bottom8=true":  { "model": "bottom_panel_8" },
        "Bottom9=true":  { "model": "bottom_panel_9" },
        "North1=true":  { "model": "north_panel_1" },
        "North2=true":  { "model": "north_panel_2" },
        "North3=true":  { "model": "north_panel_3" },
        "North4=true":  { "model": "north_panel_4" },
        "North5=true":  { "model": "north_panel_5" },
        "North6=true":  { "model": "north_panel_6" },
        "North7=true":  { "model": "north_panel_7" },
        "North8=true":  { "model": "north_panel_8" },
        "North9=true":  { "model": "north_panel_9" },
        "East1=true":  { "model": "east_panel_1" },
        "East2=true":  { "model": "east_panel_2" },
        "East3=true":  { "model": "east_panel_3" },
        "East4=true":  { "model": "east_panel_4" },
        "East5=true":  { "model": "east_panel_5" },
        "East6=true":  { "model": "east_panel_6" },
        "East7=true":  { "model": "east_panel_7" },
        "East8=true":  { "model": "east_panel_8" },
        "East9=true":  { "model": "east_panel_9" },
        "South1=true":  { "model": "south_panel_1" },
        "South2=true":  { "model": "south_panel_2" },
        "South3=true":  { "model": "south_panel_3" },
        "South4=true":  { "model": "south_panel_4" },
        "South5=true":  { "model": "south_panel_5" },
        "South6=true":  { "model": "south_panel_6" },
        "South7=true":  { "model": "south_panel_7" },
        "South8=true":  { "model": "south_panel_8" },
        "South9=true":  { "model": "south_panel_9" },
        "West1=true":  { "model": "west_panel_1" },
        "West2=true":  { "model": "west_panel_2" },
        "West3=true":  { "model": "west_panel_3" },
        "West4=true":  { "model": "west_panel_4" },
        "West5=true":  { "model": "west_panel_5" },
        "West6=true":  { "model": "west_panel_6" },
        "West7=true":  { "model": "west_panel_7" },
        "West8=true":  { "model": "west_panel_8" },
        "West9=true":  { "model": "west_panel_9" }
    }
}