I had at one point some nice fabed aluminum brackets that put the strut donut (as a I call it) on top of the tower. The key bit was a spacer between the spring cone and the bearing plate. The one pictured does the job but as noted the Nissan Comp manual as a better way to acconplish the job.......I agree that slotting the donut plate looks iffy.

So assmebly of that strut from spindle up would be: Strut,Spring,Spring Cone, Appropriate Spacer, Bearing Plate into the underside of the strut tower then the strut donut bolted on top.

Tom