I think you have a very good chance, cause if you are below their 50% it doesn't matter how much you below. Also, ucla is trying very hard to improve their ranking i guess, they will need some high lsat taker.
honestly since your track record shows you've been scoring well overall i wouldn't. I advised my friend (who recently began IL at ucla law) who first scored a 159 to write one since he's had a demonstrated history with test anxiety.