Stepside Question--Help

[jc1]

Im trying to save a few bucks and put universal LED tail lights on my 1980 stepside. Needless to say, Im having issues or I wouldnt be asking for help! I cant find the wiring diagram for the plug ins on the side of the bed. THe top grommet has two blade connectors in it, the bottom one has 1 blade connector. Any help on which part of the tail lights these are connected to would really help me. And also, any ideas on how to ground these as i think that is my real problem,

Thanks!