The original Kenmore Model 158 sewing machine used a two-wire line cord:

In light of my modifications, grounding the frame seems prudent. The heap produced a long IEC extension cord with screw-mounting ears on the socket end that fit neatly into the GX270’s rear panel area occupied by two PCI cover plates, so a bit of Quality Shop Time seemed in order.
The GX270’s carcass yielded a complex bit of sheet metal that held the hard drive and a few other odds & ends, with some clean right-angle bends in exactly the right places:

Some bandsaw work removed the gimcrackery:

More bandsawing produced a rough outline:

Sawing to length, removing the small flanges, and squaring the sides:

I traced the existing PCI cover tabs, bandsawed the outlines, and filed to suit:

They look a bit ragged, but fit well enough:

From the outside, it looks like it grew there:

The divider between the PCI slots succumbed to tin snips and a bit of filing. The tabs climbing over the bottom edge come from the internal EMI shield covering the entire back surface.
A bit of coordinate drilling and manual milling produced the IEC socket outline

Which looks pretty good from the inside:

And great from the outside, if I do say so myself:

Match-drilling a #6 clearance hole below the hole in the clamp arm, then ramming a self-tapping case screw into it, provides a convenient grounding point for the sewing machine cord:

The chassis lid has two matching holes for those screw heads, which would ordinarily hold the two PCI cards in place. I could remove the clamp arm, but it doesn’t get in the way of anything.
I loves me some Sherline mill work…