It ended snapping off the housing just below the O ring and the next section is still stuck in the block.
Wow . That is one for the books .
Yeah...rather strange since the distributor, as an assembly, has the drive gear and rolled pin that helps to shove upwards when you tried with the "oil pump shaft approach" from below.
Is the stuck part just the bottom half of the bare housing now? I'm thinking maybe you must have sheared off the rolled pin and the shaft came out? Or did just the aluminum housing twist off at the O ring (filter wrench approach)
I have found that a somewhat sludgey engine can cause them to stick pretty badly. At the salvage yards this was the common answer, that is to go at them from below with oil pump off. Makes me recall when I once had one in a 351M that couldn't be moved to even adjust the timing, in a California, rust-free environment...nothing to do with corrosion. I never did get it to adjust or come out, but always believed if I had pulled the pan and went that way...it would have come out. Now I wonder if that example wasn't stuck as bad as yours is.
Good luck, but let us know how you got it. Might try soaking the lower housing from below with a spray carb cleaner, drive it up and down, spray again and repeat. Maybe the sludge has it stuck because that occurs below the O ring
Richard