Note: This hasn't been on my framework for long, and I am not sure it'll hold up or stay flat.

Here's the process though:

Materials I used:

1. 1/16" walnut ply sheet (usually for laser cutting)

2. Existing spacers to canibalize

3. CA glue (I used starbond, but any super glue really)

4. Wipe on polyurethane

Tools needed: whatever you need to cut your material! I used a box cutter and a ruler, but a laser cutter would be ideal.

Process:

1. Print the 3d piece. No supports needed, just place it flat side down. Once it's done, it'll be very thin and hard to remove from the bed. Don't worry too much if it gets a bit bent up when you pull it off.

2. Cut the wood/sheetgood piece. I did this by tracing an existing spacer onto my wood, then cutting it with a ruler and multiple (many) light passes of a box cutter. Make sure to not include the tab at the top. The end result is roughly 33mm x 114mm but I just did a dry fit and adjusted it until it fit nicely. I sanded the wood lightly with 400 grit sandpaper and coated it with a few coats of wipe on polyurethane. Make sure you put the same finish on both sides, as it'll help to prevent warping.

3. Glue the flat side of the print to the wood using a small amount of CA glue. Positing the 3d printed piece so that the tips of the two thin lines at the bottom are exactly in the corners of the wood.

4. Remove the rubber pad from the original spacer. I was able to do this by just prying it up with my fingernail. 

5. Remove the metal piece from the original spacer. I did this by gently rocking it back and fourth until it came free. Be careful not to bend it.

6. Dry fit the metal piece and the wood to see how it lines up.

7. Glue the metal piece into the spot between the two thin pieces we aligned to the corners earlier.

Let the glue cure fully before putting the spacer onto your laptop. You don't want CA glue dripping into your computer and you don't want the spacer to get stuck.