Marcos Maniacs

Hello Maniacs,
I need to remove the brake backing plate from the rear axle. My car 
#3M 5463 has the (removable, ha!) hubs. I've tried a heavy duty hub 
puller, as well as a slide hammer (to remove the whole axle, hub and 
all) with no luck. Since the backing plate has to be removed to get 
the diff assembly out.....my only other choice is to cut the frame 
(it's rusty anyway and has to be replaced).  
Any ideas?
Regards,
Hampton Peterson