I just bought an used olser emark mower. There are two numbers on the side where the serial number is supposed to be. The numbers are stamped into the tag but the writting is all gone. They are M48-14k-5 and 91047. Can you give me a build date and send a manual (I have been reading some other posts and you said this was no problem...). Thanks! I also have a question regarding the upgrading of some of the components. Is it possible to upgrade the spindles to the newer ones without the grease fittings? Thanks in advance!!