I installed a rear wheel spacer kit on my B7800 today so I can use chains. It adds 1 ½" between the side of the tire and the sheet metal. Not complicated but took some time. Here is a video as that is easier than trying to upload photos on this site.
https://www.youtube.com/watch?v=aIEOWDxnd2E
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https://www.youtube.com/watch?v=aIEOWDxnd2E
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