I have an 08 LR3 with the full SYA kit and straps, and rhino lift rods plus the gap tool to raise it beyond. Overall about 4” lift to fit 33.2” tires. 275/70r18 General grabber X3 (love)
Arnott air struts are the best in my opinion but I’ve used the Atlantic British ones with great success too. Replacing all 4 is really the way to go. The air suspension valve blocks are all very easy to get to, the rear one being by far the most frustrating. If you are replacing the struts and adding the spacers just run longer line to the driver rear strut and make it easier to do the rear block. There’s nothing difficult to replacing nearly every part of the air system. The electrical wiring is another story.
I’ll also confirm not to go greater than 31.5” without the SYA kit and trimming frame horns up front and relocating the heater hoses out back, then flattening the body seam fin out back too. Some will say wheel spacers are the answer but that’s got too many geometry/weight/stress concerns for me.
The biggest reason to do the kit and rods rather than just the gap tool is a fail safe and with the spacers, your struts are at much lower pressure and the ride is much better. Then you still have the option to go into off road height and extended until the straps limit that. Just know that every inch you raise these beasts you are loosing in downward wheel travel... something you will miss bit is not detrimental.
