The last 3 digits are taken off to get the serial number. So your serial is 169 761. The 427 is the transmission code, which is a regular speed transmission, short pinion shaft (non- 4wd). Early 1850s used this transmission, as well as 1750s.

285 = 1850

1 = narrow front
1 = gas engine
002 = ???

Your tractor is a 1966 model.