727 Difference inside

coyote42 said
Here are the numbers on both transmissions.

View attachment 1716171545

View attachment 1716171546

Sorry to be so late to chime in. I'm agreeing with the others on the 373 trans. It's not in the application chart I listed, and I don't have access to a 1973 truck parts manual. But Google sources call it in favor of that.

Is it snowing there yet?