Disc TO Drum Conversion Help

[nonstop]

The title sums it up! It looks like I will likely be converting BACK to rear drums on my truck, specifically so I can have a functioning parking brake if/when I take out my Spicer 5831 (where the current brake is mounted).

So I am gathering parts, and have hit a little bit of a road block. I would like to mount slip on drums instead of mounting them behind the hubs. Is there any way to do it without changing axle housings? I have searched and searched, but am coming up empty. Does anybody make a backing plate spacer, or am I overlooking a simple solution?

Thanks,

Nick