I have a lower unit I'm having trouble identifying. It has a 3 1/2" hub. Is 17 1/2" from bottom of skeg to top mounting surface and 7 1/2" from center line of hub to cavitation plate. the kicker is it has 5 vertical slots above the cavitation plate and 4 water intake holes below cavitation plate with internal screens. can anyone help with what it fits. I'm stuck.

