Tyler,
Just had another look. I assumed the mower date of manufacture was 3rd January 1999 (1399). Perhaps they use a different system.
As you said, the engine is earlier - 1988.
All very intriguing, an engine swap sometime ?

Thanks
Alan

Attachments
Murray DOM .JPG (61.2 KB, 54 downloads)
Briggs DOM.JPG (48.44 KB, 52 downloads)