Turns out my ramp optic fiber clips can also hold a piece of plastic hobby angle against a ramp. Comet strips then stick straight on.
I only have red and blue Comet strips at the moment so I hooked them into my controlled red and blue strings, but I'm getting some white ones and simply plug them into the nearest spotlight!

This is just a quick first hook up. I haven't even tried to hide or tidy up the wires.

Video at the bottom. I have only done the left side, so you can compare.

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Indeed. Like AC/DC. One comet strip, one piece of 3/8 Plastruct ABS angle.

Comet strip extends below the bottom of the angle. Use the protruding part of the comet strip to adhere to the ramp. The whole assembly sits at a slight angle so the LEDs face down towards the playfield and the top edge of the angle acts as a cowling. Pretty close to invisible at player angle.

Comet strip plugs straight into the adjacent spotlight.

The left side in the last pic still has the 1/2" angle that I tried first. I think it's a bit big. I prefer the 3/8".

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