The bullet tray, empty case tray and a powder mirror like this one from Amazon are great upgrades for the 550. Case feeder would be nice.
I also upgraded the shell plate bearing and primer slide with a roller bearing.
HARDK Inspection Mirror Magnetic Base Welding Magnet https://www.amazon.com/dp/B07HNBWJ3M..._66W9DbW729TZG
One wrap of electrical tape holds it in place
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