What kind of torque converter is this? Itt has a drain plug and has 27t spine but it will not fit on a GM 700R4 shaft. It was sold to me as a companion to the transmission, but it is not.
The plug was added by someone who drilled a hole into the converter to drain and flush it. It's not a lock up converter, so it can't be for a 700. you can tell because the face is not "square" around the outer edge, since there's no lockup clutch in there. The rectangular lugs were used on the TH 400 converters, as the TH350 converters for Chevys had tabs, and those for Buicks had small square lugs. So it's probably a B3, if you're looking in a Dacco catalog. Fits most GMs with TH400 from 1965-1990, but not the trucks or vettes with the 6 lug converter. https://www.buffaloengine.com/catalog/p-100913/gm3-b3-th350-th400-th475-torque-converter