Ches - yep, that was the original clamp, but it had seen much better days and was closing up before it could clamp up the pipe properly, so it was replaced by a much heavier 'U' type - the sort of thing that you would normally see on, say, the joint between a silencer and a tailpipe.
Les - yep, did that, just like you say, but just couldn't get the elbow and the downpipe clamped well enough to stop leakage. Someone else has said that there are two downpipes with differing lengths. If that's right, then this must be the 'short' one which is possibly why it won't clamp up correctly.
Having worked on quite a few vehicles over the years and this being the first LR, I have to say what a useless design it is - I can't see the point of the "double-skinning". To cap it all, the next joint along (downpipe to silencer) is two flanges with a spherical sealing face - just the job for the manifold to downpipe. Why couldn't they have used that design??
