Thanks for the info. Fla54Chevy3100, the table was great. It looks like I might have either a 1352-000-216 or 1352-000-257. Is there any way to figure out what year they were produced? Mine says Borg Warner on the case. I know that Tremec took over production at one point and may have either used the Borg Warner cases or had part numbers for overlapping production. My guess is that that lower number (216) makes most sense.

Thanks again to everyone for the help.