Identify my TH-400.

[RichSchmidt]

I have a TH-400 race trans that is about to go into my race car. For giggles I decided to read the tag on the side of it. It says that it is a 1972 trans but has the code CR. The only CR I could find is for a 1970 LS-5 in an A-body. Would a service replacement trans have the same code but with the new year on it? The trans seems to have no VIN. I have multiple lists of codes and none show CR for 1972

Here is what the tag reads top line 7?R in yellow letters then 355 stamped in. Bottom like stamped 72-CR-6237

Thanks