Torque converter ID?

[goose]

A friend of mine just gave me a torque converter that he says is out of a Torqueflight. He doesn't know anything other than that. I cleaned it off and couldn't see any readily visible identifying marks... anybody know how to tell whether it came from a 727 or 904, or what engine(s) it may have originally been used behind, etc? There don't appear to be any balance weights on it although there are some marks around the drain plug that look like something possibly was cut off from that location at some time.

[6 packin]

If you can look at the tranny!
Tell me the casting number I will get back to you in a flash. its
located on the driver side just above the pan rail, on the case. It can be tough to find. I will tell ya every thing about it.

[goose]

Therein lies the problem... all we have is the converter. Are the converters interchangeable between 727 and 904?

[nhdriver]

727 & 904 Converters do not interchange. Also 66 and earlier convertors do not interchange (on 727's) with later ones.

[goose]

Is there any way to tell if it's a 727 or a 904 converter?