Length is fine, I just had some confusion about what *exactly* was considered Standard by the reference client. I searched for a while to find any topics discussing the exact bytes in the scriptPubKey and couldn't find anything. So hopefully this helps anyone going through the same process.

99% of the time, OP_RETURN scriptPubKey will be (in hex):

  6a

If you need 76 - 78 bytes of data... add an OP_PUSHDATA1 (0x4c)

  6a 4c