Though chainsaw mills do have their place, I found them painfully tiresome. For a log that big I’d try and find someone with a portable bandsaw mill to cut it. After cutting my first 100 board feet of lumber with a chainsaw mill, I was ready to find a
Wood Mizer. The chainsaw mill I had used about 10x the gas for the same number of boards as my band mill. Better quality lumber, less planing, and more board feet will be salvaged with a band mill over a chainsaw mill. If you do end up going diy with the chainsaw, a ripping chain on the absolute biggest saw you have would be good.