I agree, ThunderRanch may be able to help you, since they are building the RSK on a tubular ladder frame and I am pretty sure they also have some information about the space frame and suspension.
I couldn't find the frame, but from what I can see from pictures it is very similar to the 550A space frame, but it looks like they used coilovers and A-Arms on the RSK. The center seater was a little different.
(Message Edited 2/20/2003 1:26:04 PM)
(Message Edited 2/20/2003 6:56:40 PM)