I'm not sure if Garmin considered to have the option of cloning your device on a FAT 32 formatted SD card, but it is helpful.
Your Device only has 8Gb not enough for Europe or North America, GE looks at the available space and on other devices offers you to use an SD card to extend the storage. Your nuvi 58 Travel Edition does not give you that as an option, instead only presents maps that will be able to fit.
I used a 32Gb SD card to clone your device, so plenty of space. Try it yourself create a folder called Garmin and place a copy of your garmindevice.xml in it. I did rearrange the update files I uploaded for you so it could be used as supplemental maps gmapprom.img to gmapsupp.img etc. Your newer device can use custom names like EUN.img & EUS.img
Spoiler: Map choices
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