Help getting flange off??!!

Tooljunkie said

The way you were planning with the screwdriver should work. I
Have chiseled the seal,to collapse it then it almost falls out.

Click to expand...

So.....Used the "tap one end in and pry the other" method and got the seal out. Hammered a screw driver into one side of the seal and after a bit of prying it popped off. New seal in tomorrow. Thanks everyone for the help!