I once owned a '62 Chevy that was factory with a 283 and cast iron powerglide. There was an adapter ring between the transmission and the motor, and I understood there was a different ring for the sixes.
Could it be that finding a V-8 type adapter ring from an early cast-iron powerglide would allow using a 230/250/292 with the early transmission?
I've no idea, and no intention of doing such a thing, but it might Ben's problem...
