OK... I think I fixed the pushrod issue. I took a 7/16 by 20 thread by 1-inch bolt, cut off the end, and used a long nut to attach it to the end of the pushrod. Now I have 1/2 inch of pedal travel as expected.
Now, the next problem. I can bleed the front brakes, but I cannot bleed the rear. I noticed during bench bleeding of the master that only the front reservoir was bleeding. There was no movement in the rear reservoir. I thought I had a defective laster (bought from AutoZone new, not rebuilt), but I realized that if I push the master in further, the rear would bleed. It seems the rear engages a little less than 1/2 the way in.
Now, when I press the brake pedal, I can see fluid pushing up in the front reservoir instantly. About 2/3rds the way down, the brake pedal gets hard, and the front drums engage. Before the hard part in the pedal, the front drums do not engage.
I hope I am doing something wrong or, at worst, the master is defective, but I would hate to find out at this stage that this idea will not work. Again, any help or insight would be greatly appreciated.