Boatpoker beat me to it! I have the engine handbook for mine which says:
"The serial number is stamped on the fuel pump mounting flange of the cylinder block
as shown in Fig. 1.
A typical number is TU30048U510123E (see next page)"
I have this in .pdf if you want me to send it to you, that would be easier than trying to extract the images and tables and post them somewhere. Just PM me.