Hi John, the engine number is theoretically 1928.
The main changes for 1929 were no thru the tank compression release, and the machines left the factory with drop centre rims, not clinchers.
1928 hubs rode on ball race bearings,, which were changed to a Timken taper roller for 1929.
Not a lot of difference elsehere tbh.
Your bike looks like a great find. Congratulations.