Ultimate Replicator 1 Octave Filament Spool Holder

First, I want to thank the amazing folks on Thingiverse who have designed and posted some amazing spool holders for the Replicator 1 to hold Octave spools of filament, which are available for cheap on Amazon.

However, in my experience, I was not able to get a final printed example that worked very well. When I did get one to print, it didn't do a very good job of holding my spools. There was a lot of sagging of the spool, and some of the spool holders wouldn't fit into the hole on the back