  In this note, a procedure is developed to explicitly construct non-trivial
F-theory lifts of perturbative IIB orientifold models on Calabi-Yau complete
intersections in toric varieties. This procedure works on Calabi-Yau
orientifolds where the involution coordinate can have arbitrary projective
weight, as opposed to the well-known hypersurface cases where it has half the
weight of the equation defining the CY threefold. This opens up the possibility
of lifting more general setups, such as models that have O3-planes.
