assuming I have a dropdown that I need to populate with items, but they are dynamically generated based on the dropdown that was selected before it... so... like...using the examples of vehicles... lets say i have vehicle data like this.. 
vehicleDetails.json

```
{
    "1": {
        "id": 1,
        "make": "Subaru",
    "models": [{
            "id": 1,
            "name": "Forrester",
            "years": [2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020],
            "series": [{
                    "id": 1,
                    "name": "SH",
                    "years": [2009, 2010, 2011, 2012]
                },
                {
                    "id": 2,
                    "name": "SJ",
                    "years": [2012, 2013, 2014, 2015, 2016, 2017, 2018]
                },
                {
                    "id": 3,
                    "name": "SK",
                    "years": [2018, 2019, 2020]
                }
            ]
        },
        {
            "id": 2,
            "name": "Impreza",
            "years": [2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020],
            "series": [{
                    "id": 1,
                    "name": "GJ",
                    "years": [2011, 2012, 2013, 2014, 2015, 2016]
                },
                {
                    "id": 2,
                    "name": "GT",
                    "years": [2017, 2018, 2019, 2020]
                }
            ]
        }
    ]
},
"2": {
    "id": 1,
    "make": "Toyota",
    "models": [{
            "id": 1,
            "name": "Camry",
            "years": [2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020],
            "series": [{
                    "id": 1,
                    "name": "XV40",
                    "years": [2009, 2010, 2011, 2012]
                },
                {
                    "id": 2,
                    "name": "XV70",
                    "years": [2017, 2018, 2019, 2020]
                }
            ]
        },
        {
            "id": 2,
            "name": "4Runner",
            "years": [2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020],
            "series": [{
                    "id": 1,
                    "name": "N210",
                    "years": [2009]
                },
                {
                    "id": 2,
                    "name": "GT",
                    "years": [2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020]
                }
            ]
        }
    ]
}

```

}

I three inline drop downs that show make, model, and series. I need it to only show models that are related to makes, and series that are related to models. but these are nested arrays and a v-for only handles one array at a time. And the id's don't seem to be relevant to each other... like.. the id of 4runner is the same as Imprezza. Struggling here. Help?