Picked up a 904

it is a large register
stamped into the wall just above the pan is:
PK 3681841 4681 4592
these numbers were stamped in really deep and ez to read


and got these number off the small register 904 in the 68 Barracuda,
538368 Y 226 3297, same location as the tranny above
the stamping on this case was very light,, not easy to see,,

can anyone interpret these,, any info on date of manufacture,, maybe ratio info?

thanks

3681841
early‘74Charger,Dart&Valiant,6cyl.
early‘74DodgePass.&PlymouthPass.,6cyl.,
A904

Given that, if the guts are still stock, it will have the typical A904 gear ratios.