I had those same wheels. They look AWESOME. Especially on a MGM 4Runner. They are a bit too wide IMO. You can make them work if you're dedicated to the idea, but I wouldn't expect much room for flex. I had 285/75/17 and needed BMC and BFH along with UCAs. Did not hit UCA though. I'm sure you can go on the BFG website and see if the 275 is made for a 9.5 wheel. I bet it's at the top end, but probably ok. Good luck.
@dak1b you would also need hub centric spacers. They are hard to find in the 106/112 size you will need, so be sure to ask the seller for them. It's a good idea to have spares too. Different brands/models of tire have different tolerances. I had 285 Toyo OC AT2 Extremes on mine. They didn't look weird, didn't drive weird, didn't wear weird, and were within manufacturer spec on a 9.5 wheel. I believe the Falken Wildpeak 285 is also manufacturer approved for a 9.5, but I'm not 100% certain. Their website will tell you.