You would need an adapter ring from an early V8/Powerglide vehicle. I don't think they made a different transmission case for the V8's, and the 6 cylinder models definitely used an adapter. It's a cast iron adapter about 2" thick on the 6 cylinder models, but that one will have a different block bolt pattern than the 8 cylinder. Your 250 has the same bellhousing bolt pattern as the early v8's did.

A cast iron Powerglide would be the worst possible choice of automatics for most uses. Any reason you're choosing that one?
Jerry


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