Can anyone tell me about suspension maintenance?

[alanplumbridge]

I'm on my third Caterham but never had to maintain one myself before, until now. My current car is a 1998 1600 k-series, 138bhp, dry sump, LSD, wide track, DeDion. I've got a few questions for you oily-fingered lot if you'll indulge me. Where to start...
As my car has a dry-sump, can I assume it won't have a foam baffle that needs periodic replacement?

I'm trying to cure noises from the rear suspension. Two rattles vanished when I renewed the anti-roll bar drop links, but there's still a rubbery clonk coming from one side on very bumpy roads (roads so bumpy I need to drive at less than 20mph). Where's the most sensible place to start replacing stuff? What are the most vulnerable parts? On my old live-axle car, it was the A-frame apex bush. What is it on these DeDion cars?

What's the deal with the two alternate mounting points for the radius arms? Mine has them attached to the lower mounting. I can see that if I changed them to the upper position, it would introduce some rear steer in the opposite direction to the front wheels (rear wheels turn right in a left-hander). What's the consensus about whether that's a good thing or not? Most peoples' build diaries say 'I've gone for the lower attachment' which is the 'race' setting, who uses the upper attachment 'road' setting? Is it easy to change the radius arms' mounting position from one to the other? Advice much appreciated.