Brake Adjustment Hole - 1978 K30 Dual wheel

[68_Step]

I talked to the local auto parts store and they call the drum manufacturer and they said they stopped making 2 versions of that drum (one with the adjustment hole, the other without it) - they now only make the version that does NOT have the adjustment hole.

Do I need an adjustment hole in the drum or the backing plate? I thought I needed one for either the rough adjustment to start or to back off the shoes in an old drum...