Identifying a Logic Module

Ever wondered what those three digit numbers hand written on the logic module for 1984-1987 made Chrysler vehicles?  They actually are the last three digits of the part number of the logic module itself.

From 2012-2013 Mopar Reman Catalog

 

 

More than likely, writing the number on the circuit board itself prevented confusion when the board were inserted into the case at the factory.