Apple IIe port covers, thicker for FFF printers

thingiverse

option8's [Apple IIe port covers, three sizes](https://www.thingiverse.com/thing:1644153) are really nicely sized, but the lugs on them are far too thin to be robust. I remixed their designs in OpenSCAD to make them stronger. The port covers now have tapered edges to make them easier to remove from the print plate. I'd recommend printing in PETG or something not too stiff as these are quite snug. If you want to run the OpenSCAD scripts to generate variant designs, you'll need to download option8's original STLs to the same folder as the OpenSCAD script. A couple of variants on the 19-pin Disk II connector cover are included: * one has a round hole suitable for a [Mini Panel Mount SPDT Toggle Switch](https://www.adafruit.com/product/3221), maybe for a speaker switch; * the other has a hole for an Apple USB keyboard extension cable, which might be useful (if not recommended by the developers) as a way to bring the USB slot from a [BOOTI card](https://ct6502.org/product/apple-ii-booti/) to the back panel.