Don't have any non-oily lubricants around, I sprayed a cotton swab with WD-40, dried it, and dabbed the residue on the ends of the stabilizer bar.
No more squeak, and no WD-40 everywhere, either.
I'll pick up some less messy lubricants for future use, though.
I'm interested in finding out how to remove the key from the white stabilizer clips in case I want to strip down and clean the keyboard a few months or years down the road. Last time I tried forcing something electronics-related was my first PCIe graphics card, turns out that motherboard had a retention clip on the slot; One crunch later, and I had a chunk of retention clip clinking around on the motherboard. Whoops.
Glad that worked out
There are two real concerns with removing the large keys: 1.The stabilizing bars are very precisely bent, a millimeter of incorrect bend can cause problems. And 2. The backplate mounts that support the bar are made of plastic that can break if you're not careful. I'm reluctant to share the details, since it might be viewed as my approval that everyone do this, BUT I'm of the "give condoms to kids or else" philosophy, so here's plan B for when you just can't control yourself
DISCLAIMER: If you are going to follow the instructions below, please be aware that damage made by you while performing this procedure on is NOT covered by your warranty.1. Each large key is supported by 1 switch flanked by 2 white plastic bar clips on either side. While not necessary, removing small keys around the large key of interest, may help in removing the large key, since keycap tools generally do not fit something the size of a spacebar.
2. Use a keycap lifting tool or your fingers and GENTLY wiggle/lift the key until it slides off the center keyswitch.
Careful, you do NOT want to just yank up on the keycap and detach the white bar clips from the key cap in one fell swoop! At this point the keycap will be attached to only the white clips which in series are connected to the stabilizing bar; the stabilizing bar is connected to two black plastic mounts connected to the backplate.
3. Now that the cap is released from the center switch you should be able to hold the left and right sides of it with your fingers. Hold both sides firmly and carefully pull up on one side just a bit, you should feel the keycap begin to slide off the clip, you might need to pull the opposing side and alternate between pulling sides until one side comes off. HOWEVER, only release one side first! THEN, carefully note the orientation of the clip as it is not a symmetric part and must be correctly re-oriented when you put the key back on for it to work. Each clip actually has a long side that should point toward the back of the keyboard for the Shift keys. (Other keys you should examine!)
[strike]4. Once both white clips are detached, you can set the clips and the keycap aside. At this point the bar must be removed. Why? Because otherwise you will spend an hour trying to precisely balance those wiggly clips on the bar while trying to put the keycap back on; not recommended. The bar can be removed with your fingers or a pair of needle nose pliers. Firmly grasp one side of the bar (the vertical L-shaped region) directly above the backplate mounts. The black plastic bar mounts open towards the front of the keyboard for the Shift keys; this is the point where you can break something EASILY - so very carefully pull the bar forward while providing a small amount of downward force. This shouldn't take too much power, just DO NOT PULL UP, as you can break the mount! The bar will release from that side the mount. Repeat for the mount on the opposing side.
Note: At no time should you try to pull the bar from the center. This is good way to bend the bar irreparably. Always grasp the bar near the L-shaped turn where it is structurally the strongest.
5. Replacing the key: Reattach the bar to the keycap using the white clips, be sure to orient the long side of the clips correctly as previously noted. At this point you may want to put a bit of your grease of choice on the mount or the bar or both; sparingly of course. Next hold the assembled key/bar combination and position the bar near the mouth of the backplate mounts. Employ your needle nose pliers again and firmly grasp the bar on one side below the clip in the same way you did to remove it. Gently push one side of the bar back into the mount. Repeat for the opposing side.[/strike]
EDIT: I've subsequently found that the bars on the FILCO do not have to be removed in order to replace the keycap. Instead you insert the white clips back into the keycap in the proper orientation. Then attach one clip to the bar and gently push it to one side, parallel to bottom of the bar, with a little bit of the force the L-shaped part of the bar will bend slightly and the second clip will slip into the L-shaped bar on the opposite side. The bar has enough spring to it that this won't permanently bend the bar and the clips are made strong enough that they shouldn't break. This method greatly simplifies the removal/replacement of the large stabilized keys. I recall trying this on other boards in the past with mixed results, but works well on the FILCOs.Done. I guess a video would have been easier, but there it is in writing for the visually impaired among us.
Reminder, You break it = TOO BAD!