A couple of things. First and foremost, go through the threads! This is a topic that has generated a lot of ink.
Second. The short answer is 265/65R18, no cutting, it just fits.
And lastly, when you start pondering the idea of bigger tires, >32”, you start running into problems. Some are minor and perhaps tolerable, others, not so tolerable and it will require surgery. I strongly suggest you check out
Expedition Portal and read
The Modern Explorer: Land Rover LR4 - Part II. The author, Scott Brady, addresses your issues head on and it seems you are following his path, weather you realize it or not. He ultimately went with the Falken WildPeak's; 265/70R18. (33x10.5 R18). The common denominator between his build and what I have, is that we both went with 2.5" lift via Johnson Rods and an off-road front bumper. He went with an ARB and I choose Tactical 4x4. And still he had some minor fitment issues with the tire size.
I did things a little differently when it came to tire selection. Mr. Brady opted for tall and thin; 33" x 10.5". I went with Mickey Thompson Baja Boss A/T 275/65R18 (32.5x11). Slightly smaller and slightly wider. For that to fit I had to cut the frame horns. (Cost is about $200 +/-).
For everyone's edification, I have attached my
Tire Selection Matrix which I created to aid in my tire selection. My primary consideration for getting the tire I wanted was the Three Peak Mountain Snowflake rating.
Now a "shout out" to the good guys at the America's Tire Store in Huntington Beach, CA. They allowed me to test fit a number the tires without any fuss. A word to the wise, test fit your tires first, BEFORE you buy them.