I posted this in the 'Saved From the Dump' thread but thought I would post the serial number here. It is WF13 313. Here is what was posted in the other thread:

I picked up this '87 Nishiki Cresta GT recently and just finished up a complete overhaul. I had picked this up with the intention of turning it into my wife's work commuter however it is too bike so I will pass it on to someone else. It is a touring bike that had flat bars when I got it. I put on rando bars and swapped the 5 speed freewheel for a six speed. I have $41 into it. I apologize for the bad picture but it is too late to take a picture in the wild.