In standard eighteenth-century voice-leading practice, inverted seventh chords must be complete. This changes in more modern practice, but when you're practicing voice leading in this specific style, keep those inverted seventh chords complete.
As such, you're 100% correct. Since the inversion determines the bass note, that determines what three pitches need to be present in the upper voices.
||Bass Scale Degree
||Upper-Voice Scale Degrees
||5, 2, 4
||5, 7, 4
||5, 7, 2
When in root position, however, then you can omit the fifth (scale-degree 2) of a V or V7.