I have also been looking at alternatives for the steel wheels for the 410. One option are alloy replicas of the steel wheels which SHOULD allow for both the fitment of Bristol's 'big brakes' and the original hubcaps.
I am not sure that will be possible and am still waiting to get wheel info from Bristol (the PCD is known, but I need the offset 'ET', the rim width and rim lip type). If anyone has the newer alloys in 15" or 16", that info should be stamped inside the wheel (need to take wheel out unless you have a spare alloy).
Here are some pictures (click to enlarge):
Ccapfullceramic2.jpg
Cnocapbrushedpolisherim.jpg