|Wrong! So wrong!|
Woe! Alas! The horror! They included four port-side male sponsons, instead of two each of port and starboard. I failed to notice until I'd already magnetized them all and tried them on for size.
I've emailed Battlefront about the issue, and hopefully they'll be sending me some replacements, but until then they'll have to be used as either female or hermaphrodite tanks, since I appear to have a full complement of female sponsons.
I feel so hurt, so betrayed.