I'm in the Process of making my own Gamecube Portable.
Since i use a slimmed Wii Drive for the form Factor, i found no solution on how to install a top loading Spindle. So here's what i came up with:
1. I bought some Laptop DVD Drives. I got 2 in my Area for 10€ total (5€ each) and considering that a Spindle costs around 6€ new, it's a good deal. That's what they look like:
2. Extracting the Spindle that looks like this:
3. Firing up Fusion 360 and remodel it as close as possible while adding fitting Hole diameters for the Wii Drive Motor:
Improved Version with 2 Parts. After inserting the springs and stuff it's glued together. Also much more print friendly since they can be printed as shown.
4. Print it out and installing the Springs and pulling pieces:
Image is on the Way.
I admit it looks not perfect but this is the first Version. I will try to improve and run some tests. From the raw measurements, nothing regarding Motor height and such has to be adjusted (Theory), but that has to be tested further.
If someone is interested in the Files (Current State V2.0) don't hesitate to shoot a PM.