Or just but big wings onto the RS2 sump if you cant get clearance at all?

What crossmember did you use by the way? I would have thought that using a world cup type you should get clearance for a Yb sump? You may need to trim back one of the lower edges slightly but it sould fit in a similar way to my Mk2 set up?

With regards to filters, you could fit an ally take off and then use a remote filter housing set up higher in the engine bay. This would give you extra oil in the lines if thats what you were after?

Or try a Accusump that holds an additional shot of oil in various quantities and gives it to the engine when required.

CheeRS