Anybody know the correct part or application number stamp on the tab of a vacuum brake power booster for a 1968 442 disc/drum Lansing car? I'm looking for the 4 digit code (the 3-digit stamp on the other tab is the date code). My 442 is a convertible with auto trans.

My research shows the four digit code may be the last four digits of the booster part number, the last four digits of the booster/master cylinder combo as installed on the assembly line, or an application number that doesn't match the part number.

The 68 assembly manual lists a part number of 5468670 for the power head assembly for Lansing-built cars and 5468692 for the power brake cylinder for several plants, including "M"/Lansing cars. Both part numbers point to the power booster. The master cylinder is labeled as such separately. The 1972 parts catalog lists 5468670 for the cylinder assembly, power brake power assist for both 68-69 F-85 models. This would seem to indicate that the code stamp I'm looking for is either 8670 or 8692 - is this correct?

I'm curious what number stamps those of you with original boosters have on your 68 disc/drum cars?

Thanks for any assistance - Don