8.75 - 741 & 489 Rear Ends Worth Restoring?

Greetings!

Are these 8.75 - 741 & 489 Rear Ends Worth Restoring? Or are they junk?

Also is there a 8.75 for A bodies and a 8.75 for B bodies. Or are they all the same?

Thanks for the help...

Alec