So after 23 years I am replacing my original starter. I got the 3 bolts off, they actually broke off since the threads were corroded. Now it still wont come off. Do I have to hit it with a hammer to get it loose. Maybe drive some kind of chisel wedge into the flange. It seems like the corrosion has welded this thing together. I did a few taps with a light sledge, but figured I would check here before bashing it more.

 

I think you're right. When I replaced mine a couple years ago I just removed the bolts and the starter came right off, no banging or prying anything. Maybe keep trying with a mallet hammer but just keep in mind that the corrosion probably affected the mounting surface as well, so be cautious.