Snaphsot/Restore failing on ES 2.1.2

Elastic Stack Elasticsearch
1

Every time I restore data from ES 1.6.1 to 2.1.2 through snapshot/restore it is failing.
ES migration plugin gave an "advisory note" that index is good to upgrade but restore is failing in ES 2.1.2 with the following error:

{
  "error": {
    "root_cause": [
      {
        "type": "snapshot_restore_exception",
        "reason": "[stage-05-2016:05-05_1906] cannot restore index [stage-index-0] because it cannot be upgraded"
      }
    ],
    "type": "snapshot_restore_exception",
    "reason": "[stage-05-2016:05-05_1906] cannot restore index [stage-small-contacts-0] because it cannot be upgraded",
    "caused_by": {
      "type": "illegal_state_exception",
      "reason": "unable to upgrade the mappings for the index [stage-index-0], reason: [Mapper for [_id] conflicts with existing mapping in other types:\n[mapper [_id] has different [index] values]]",
      "caused_by": {
        "type": "illegal_argument_exception",
        "reason": "Mapper for [_id] conflicts with existing mapping in other types:\n[mapper [_id] has different [index] values]"
      }
    }
  },
  "status": 500
}

At least it should say which mapping type it is failing on?
I have 8 mapping types on stage-index-0 and there is no way I could figure out the mapping type.
I have been trying to upgrade to ES 2.x from past 1 month and this being my final obstacle.

Let me know if anyone can help or need any other information.

Thanks,
Ayush