Help me identify my BMW 520i's engine?

I'm trying to figure out what kind of engine my BMW 520i has in it, for purposes of DIY maintenance (oil/filter change, stuff like that, mostly). I can't figure out which one it is though.

BMW appears to have named their engines the M10, M20, M30, and M40, and some of these have what seem to be revisions (M20/B20, M20/B25...). This is true of engines for 520i's, anyways. I also know that my body style is an 'E-34' (New shape), as opposed to the 'E-28' (Old shape). The problem, however, is that I only know this from reading a Haynes manual, which claims to cover only cars made between 1988 and 1991. The book is copyrighted in 1997, so I assume this to mean that BMW changed something in later models. Unfortunately, I don't know what. I also have been unable to determine the engine size, due to the fact that I bought the car used, and do not have the original sales paperwork, or even an owner's manual (hence my purchase of a Haynes book).

Does anyone know of any good ways to identify the engine, by using the VIN, or where it might be molded/cast/engraved on the engine itself?

Thanks in advance,
Steven aka dUc0N

Bump =-P

I found out that all 520i's are eurospec... they were marketed in the US later as 525s.

And, since I forgot to mention it earlier, it's a gas (not diesel) 6-cylinder inline engine.

It's *probably* an M20/B20M engine, but if anyone knows of a way to verify that, I'd be most appreciative.

Thanks again,
Steven aka dUc0N