Topic: Bendix Master Cylinder date codes

[GT500KR]

Is there a rule of thumb on deciphering Bendix built M/C's?  I'm looking at one, presumably from a 1970 Dearborn car that shows "1378B" and  "5607C".

 

[D0ZZ70MACH]

My understanding is that cast date on master cylinders are in a Julian calendar format meaning 001-365 and are not year specific but that doesn't seem to coincide with what you found.