Bummer Dude! If you still have the broken piece it can be welded back on but the engine would probably have to be removed to do so.
between starter housing & block
no
The starter is on the bottom of the block on the side nearest the radiator.
Yes.
Weak battery, starter solenoid, or starter.
You will have to remove starter, It is behind the starter in the block.
The starter is mounted to the bottom of the engine block by the bell housing on the side near the radiator.
Yes, but the big block may need a hi-torque starter.
Shimming any GM starter is likely going to assist in better performance of the starter. It cuts down on heat radiation and vibration when not in contact with the block.
Before 2000, yes. After, no.
It is over by the starter, but screwed into the side of the engine block.
It's on the lower right side of the block