main_body_EBB_SB now differs from new standard motor plate

About mid July they updated the Stealthburner STL's, and one of the changes was to the motor_plate. The change is a modification to the large locating pin near the top of the body that fits with the main_body. No other change is apparent. This should be modified, as that feature cascades to the latch changes also. I have created a one off stl, but best if the cad could be updated. Also request that the step files for these be added.

Compare the current Stealthburner motor_plate and main_body geometry with the updated standard motor plate, paying attention to the large locating pin and cascading latch changes. Update the CAD source and add the requested STEP files; the result should match the new motor plate standard and include usable STEP exports.

Written by the indexing model from the issue text.