Getting new maps on an ancient Nuvi 660

I have here a Nuvi 660 Euro
which I got for free. It's old and the graphics look like they're from a Geocities website from the nineties, but it does actually work and navigate; I'd like to set it up in my car, so I can put on my motorcycle the smaller Nuvi I'm currently using in it. Problem is, the maps on the 660 are *very* old. I have here a set of 2016 Europe maps I downloaded the aforementioned other Nuvi, but they're in a gmapsupp.img file 3.30 gigabytes in size, and while the 660 does have a SD slot it doesn't seem to support SDHC cards, so it's limited to a maximum of 2 gigabytes.

How do I get out of this situation? I'd really like to make use of this old thing.


:mn:
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