My LED ZEP 2 pressing anything special

5-digit number of LZ 2 isn't a first press.

First press in the U.S. should probably be a Sterling with interlocking small 'ss'- that's what you typically see on the 'RL' cuts, and presumably on the issues that came out after the RL got pulled. I think Czarivey is right about the catalog number.
If you want help decoding Atlantic deadwax, here's an anecodotal thread on Hoffman. http://forums.stevehoffman.tv/threads/atlantic-atco-vinyl-labels-and-deadwax-what-do-the-codes-mean.285080/
Discogs also has matrix info for a lot of releases.
I think DK is Dennis King, but may be wrong.
Welcome to the cryptology dept'.

PS- probably a late 70's reissue Specialty Records. Scroll down in the
Discogs release info on the album and you'll see it, I think. Note that in the
comments re 'pulling' the RL from the market due to tracking concerns,
discogs says the replacement eliminated the SS because Atlantic itself did
the remaster to tone it down. It may be that your copy sounds better than
one that immediately followed the RL. The anecodotal claims were that it
sounded way too soft. I have a few old non-RL copies, but haven't listened
to them in years. In fact, somebody just sent me another, which may be a
very early remaster, just after the RL got pulled.