Neck holder for an under-the-table router

A friend has a router under the table to which he wants to add a screw-controlled lift.

The router has a 65-mm neck that can be clamped.
Here's the clamp outline (it's a 1/2 inch slab of aluminium):

Cut it out with a hacksaw, straightening the edges on a mill (yes, those Kant Twists are invaluable).

Note the use of 1-2-3 block to set it up straight. I'm shooting at <1 degree precision, nothing extraordinary needed here so just held it with the hand while clamping.

Time to sketch the clamp with a bit more precision. This is grandpa's tool, first time I do some real work with it!

And now to the rotary table to cut the hole. Need to center it precisely over the axis of the rotary table. Best would be to drill the center hole then to indicate it but no such precision needed here, so I'll eyeball it by pointing a needle at the center and see that the center stays in place while rotating.

Clamping is gonna be tough: there is not enough place to support the washer against skewing. Guess I'll try to cut out a few small pieces of the same slab, maybe it will work.

Updates to follow...