I can't really suggest anything you won't have already checked Nick, my only additional idea would be to mark the bolt heads/nuts/bush sleeves/solid mounts with something like torque seal. Just a quick line down them onto what they're bolted to. I know they're not loosening so probably aren't rotating (or at least if they are, they're rotating back), but the proper paint's thick and brittle, so it's obviously cracked if something's moved at all, even if it's just shifted fore/aft a fraction of a mm. It should show up any movement, or at least put your mind at rest about things that aren't by providing some solid proof that they really aren't. Do your KW's use an inverted damper with a bush in the strut body? If so, it's a lovely stiff design but does seem more prone to wearing out the bush than normal dampers. Definitely worth checking anyway, the rally car needed them doing at the start of this season. Also, I take it you've checked the rear beam bushes/mounts? Just in case.