No idea for RS1600i, but:

pre may83 XR3:
castor: 2d39'
camber: 1d22'
toe-out: +1 to +3 mm

post may83 XR3i:
castor: 2d47'
camber: -0d51'
toe-out: -2.5 to +1 mm

S1:
castor: 3d0'
camber: 0d00' to -2d00'
toe-out: +2 mm

Note, that the values vary A LOT for lowered cars if not corrected, and there's not that many std. height cars around.