circa 1989 Universal M25XP Serial No. 592014 or 502014?

[iyamwhatiyam]

I have two documents that conflict with each other. One states the serial # is 502014 and the other 592014, so the second digit has been mis-copied. The label on the block is smudged. I'm betting on 502014, so if someone has the same circa 1989 engine, could you kindly verify whether it is a 50* series or something else? I checked and these numbers did not make it to Westerbeke during the transition. I am assuming they get assigned sequentially. Thank you!