I have a similar set up to Ginetta's pict, (though not as shiny and pretty looking chassis...
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I found one end of the shafts in one direction had less angular movement than the others due to casting size / shaft size position etc. arrangement differences - not obvious on first glance. A bit of skillfull grinding/filing not removing much material on the interference points ( in a non stucutural area for those eng. types) increased the movement of that end by about 5 deg. and no interference in hand turning the wheels at full droop was found after. This can be viewed on the bench with a bit of careful placement and comparison of the shaft. Kind of hard to explain in writing.
Jack