After dozens of failures, Success!
It wasn't shims.
It wasn't file sharing.
It wasn't the Backups folder.
It wasn't reinstalling everything.
It was Power PC Enabler 9.0.4.
Pulled it out of System Folder, rebooted, and proceeded to hotsync without a hitch.
Running OS 9.0.4 on Lombard (G3 PB 400 Bronze) with Visor Deluxe. Syncing Now
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Allen Kelson