I would group the ali plate then move it to one side. Next, double click into the bearing block group and use the circles already on the bearing block and pull them up say 20mm or whatever thickness ali plate you're using, such as this:
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Now get out of that group and get into the ali plate group, select the circle tool, hover around the perimeter of those circles you just pulled up, you can just about see them on the top of the ali plate, then move the cursor into the centre of the circle. The tool will automatically find the centre, click once then move to the rim of that circle again and click again. That's your circle done, now you can use the pull/push too to push it down 20mm. This gives you a matching hole through the ali plate

It still won't look like a hole because of the pull up from the bearing block. So get into that group again and push the circle down by how much you raised it. you should get one hole looking like:

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Repeat for all other holes, but make sure the holes on the sketched bearing block actually match the holes in your real bearing block.

Adil