Narrowed 8 3/4 questions

Ok! Thanks for the brake help. @72bluNblu

Any ideas what the shiny metal divider is way down the axle tube that would be dead nuts center of the carrier?

Is that what the thrust button rides up against?

In my head, if i had a thrust button setup, i would be able to see straight through the axle tube.

For reference, both axles are removed in this picture and this is a narrowed axle housing with a 741 case 3:91 gear supposedly a limited slip.

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