The method in the Service manual on page L32 does indeed work.
This involves separating the pad carrier mechanism from the rear caliper by removing the two pivot bolts. The pad carrier can then be rotated rearward around the disc.
With a bit of fiddling it can then be removed via the rear of the IRS cage. There is just enough room to do this.
Once the mechanism is on the bench it's easy to slacken off the adjustment and replace the pads.
Reassembly, as they say, is the reverse.
It's a bit of a fiddle, and I did remove the front shock and disconnect the driveshaft.
