crisskro

Is there any way to back-trace the engine serial? I am referring to the serial on the block under the intake manifold.
What do those number mean? F20C2 0300033 is the code on the engine block.
My car had its engine replaced by the previous owner with one bought from the UK, and right now I don't know what year O2 sensor to buy.

http://www.lingshondaparts.com says part numbers:
2000-2005: PFKL539738
2006: PFKL539926

http://honda-europe.epc-data.com/ says part numbers:
2000-2003: 36531-PCX-004
2004-2005: 36531-PCX-014

Thanks a lot.