This might sound harsh, but being they were given is probably b/c the original owner couldn't find the connectors either. I once made a purchase from this site... Hate to say, but they were for some no name monitors already in the headrests. Was given the information that they worked and could be hooked up to a DVD player. And I thought I paid a good price for them. Shoot me in the head! Not only couldn't I hook them up to a DVD player but the harness wasn't made anymore. So basically bought something that couldn't work. Yep, my sad story.
So basically, the moral of the story, if you want headrest monitors. Purchase the monitors new and have someone install them, unless you have the skill to do so yourself.
I paid $470 on EBAY for two 7" screens made from Alpine and had them installed at a local stereo shop in my current headrests for only $300. Sounds a little expensive to some, but I got a great deal out of it. See:
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