That pic is the harness I pulled from a '96 Caprice. Any '94-96 harness from a Caprice or Impala would work as well. I am guessing the roadmasters are the same but I don't know.
For the record, removing this harness from a car requires removing the door panel, removing the harness out from the door by threading it through the hole where the accordion boot goes around, then carefully disassembling the harness. IIRC, one wire had to be cut and then reconnected in order to free this harness from the rest of the body harness.