RESTful Sensor Configuration

I have some data that looks like the sample below. I want to incorporate this into my HA installation so I can see real-time updates on train status. I’ve tried using the rest sensor to put all this info into attributes as a quick solution, but I’m having trouble using the sensor. It may be the case that the rest sensor won’t work here and instead I’ll write a custom component, but I figured I’d try the easy route first.

Once I can determine how to make any of the data available via attributes, I can probably sort out the rest. Any suggestions?

My config looks like:

  - platform: rest
    resource: example.com/wp-admin/admin-ajax.php
    method: POST
    payload: '{"action" :"get_station_feed"}'
    headers:
      Origin: snip
      Accept-Encoding: gzip, deflate
      Accept-Language: en-US,en;q=0.9
      User-Agent: Home Assistant
      Content-Type: application/x-www-form-urlencoded; charset=UTF-8
      Accept: application/json, text/javascript, */*; q=0.01
      Referer: http://example.com/
      X-Requested-With: XMLHttpRequest
      Connection: keep-alive
      DNT: 1
    value_template: '{{value_json}}'
[{  
   'Id':'17',
   'Lat':,
   'Lon':,
   'MilePost':None,
   'Name':'',
   'Directions':[  
      {  
         'Direction':'N',
         'StopTimes':[  
            {  
               'ArrivalDate':'2018-08-01T00:00:00',
               'ArrivalTime':'6:55 pm',
               'TrainId':'P332',
               'TripId':'P332',
               'RealtimeFlag':True,
               'DelayFlag':False
            },
            {  
               'ArrivalDate':'2018-08-01T00:00:00',
               'ArrivalTime':'7:32 pm',
               'TrainId':'P334',
               'TripId':'P334',
               'RealtimeFlag':True,
               'DelayFlag':False
            }
         ]
      },
      {  
         'Direction':'S',
         'StopTimes':[  
            {  
               'ArrivalDate':'2018-08-01T00:00:00',
               'ArrivalTime':'6:44 pm',
               'TrainId':'P337',
               'TripId':'P337',
               'RealtimeFlag':True,
               'DelayFlag':False
            },
            {  
               'ArrivalDate':'2018-08-01T00:00:00',
               'ArrivalTime':'8:09 pm',
               'TrainId':'P339',
               'TripId':'P339',
               'RealtimeFlag':True,
               'DelayFlag':False
            }
         ]
      }
   ]
},
{  
   'Id':'2',
etc, etc, etc}
]