4 Wheel Drive/SUVs: Siezed engine, jeep wrangler, milky color

Question
I own an inline 6,'92 Jeep Wrangler. I recently ran it through about four feet of water, killing the engine. I now face the problem of a siezed engine. I can't be sure, but I think I got water in the block. it has sat for about two months now and is showing no sign of starting any time soon.,I've removed the spark plugs and have drained the oil... a couple of people have suggested the use of Marvel Mystery Oil to free up the pistons. is there anything else I can do?  

Answer
One thing that I should have mentioned, is that when you submerge like that, you need to check all the fluids in the transmission, transfer case, and differentials.  They may have gotten water in them also, and their fluids will need to be changed.  You can tell, as the gear oil will be a milky color, and the transmission, and transfer case fluid will be a pink color.

  Carl