Timbo
Long time lurker, first time poster.
I just installed a new set (from Craigslist) of Terra Firma sliders on my LR3.
I trimmed about 4" from the area were the air compressor line interferes with the inside of the slider (see picture )
let's see, yes on getting rid of yellow knobies, no on the black ones.
I sprayed some 3M wax on the sills/rockers though not needed.
I covered the holes inside the sliders, they used crappy duct tape.
No need for the nuts, just bolt and washers.
when installing loosen the clamps to the compressor lines, same on the AC lines on the other side, it will help with sliding that inside part.
On the compressor side I made the trim just aft of that hard clamp thingie holding both lines.
When I slid the slider (see what I did there) I pushed the compressor line under and then around over towards the back.
If you use a floor jack to position the slider under the sill, you can then mark and measure where to cut.
I went conservative, cause you can always cut more if needed, as it turned out first time did the trick.
As for integrity, use your own judgement, YMMV.
For my mostly, well basically stock LR3, my new trimmed Terra Firma sliders will do just fine.
Yes I wished they offered more protection, but it would take a lot of off roading for me to justify the money and weight penalty on a mostly mall crawler vehicle.
These things should do well for overlanding and light offroading, and hopefully will absorb any damage to sills/rockers.
HTH
Edit: added pict of sliders on car
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