904-727 swap Torque converters...

What transmission was in before? Was it 904 based? Like an A500? Or a 904? If so, you have no choice. The 727 will not accept that converter.....IF that's what you're asking. It was kinda unclear to ME.
It was a 904, was just having issues finding the rite size ring gear i needed, got that sorted now, but i do have a new question lol what is this part called?

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