Duplex LC connectors can be split apart and later reassembled. With a bit of fiddling and taping things you can get a cable through a hole that's too small for an assembled duplex.
I'm going to give a try to "fast connectors" that don't need splicing, I ordered a cleaver and a stripper, that's much more affordable than a splicer. Those connector don't seem to be very popular, there is probably a reason. I already have a 1Gbps fiber media converter. I also opted for 4 fibers cable, I will try a temporary 10Gbps P2P link along the 1Gbps. Fast connectors may not be ideal with a multi-fiber cable, but I will try to make it work. The total cost seem fair.
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