i know RB20DET's are top feed, but i wouldn't think these would fit directly. I've never seen it mentioned before.
eg. R34 GTR injectors are top feed, but won't fit in the NEO RB25 (well, won't fit directly)
i guess you could make them fit, but you might need to search the 'forced performance' section to see what needs to be done. Who knows, might be an easy fix
cheers,
daniel