Welcome Rick! The B-110 was the first machine I had. Was my grandfather's since new, and we 'restored' it in 1999 in his favorite color...AC orange. I still use it for all my mowing, tilling, snow pushing, etc.
We'd love to see some pictures of your rig! Using my '68 as a reference (serial #070027), I think it's fair to assume yours is a 1968 also. I'm not sure there is any info on their numbering conventions for these machines. As noted above, the date of the Briggs is a good indicator. The serial number is tough to see, and is stamped into the steel on the shroud, below the air breather.