I just got a rebuilt/exchanged lower unit for my 1998 Evinrude 175hp OceanPro 60 degrees and already installed it. However, I have a concern, the lower unit is attached already and tighten with the proper torque, but there is a gap of about 1 milimeter or less in some sections around the perimeter of the joint, I can even see thru the other side. Is that normal? or I'm doing something wrong. I'm following the factory service manual, but still concerned. I will appreciate your feedback.