whats the difference...318 SB and 318 Wide block?

The early LA's from the mid 50's used a cast iron "Power flite" - 2 spd or cast iron "torqueflite", 3 spd,that had a different flange, then around "62" I believe, the LA came out with an aluminum "torqueflite" for a few yrs, that was compatible with later SB engines, phew , can't believe I remember that stuff, and still have hair..

The hub on the old converter had 6 or 8 studs, that stuck forward thru the crank flange and you had to reach up through a small space behind pan ,to undo converter nuts..