Broken Bolts

Hopefully someone can help or give some advice.
Long story short, I went to replace the seals in my Hayward pump and the 4 bolts that hold the motor to the basket side looked like they haven't been touched since the pump was put into service. So I proceeded to snap 3 of them off and the 4th one just turns (I'll try to get that one out tonight).
Logic and limited experience tells me that (even though these are long bolts with threads pretty much all the way) that I should be able to separate these parts when I get that last bolt out, no?
After that I will be faced with getting the broken studs out, hopefully with just some more PB Blaster and vice grips as I think drilling them out of this type of equipment probably won't end well.

Anybody have experience with this? I can't imagine I'm the only one.
I'm afraid worst case I'm looking at a new pump!