In addition to the other tips here, it would also be easier if you could disassemble the entire keyboard and lift it from the frame entirely. I’m not sure how ThinkPads are constructed, but the other brands I’ve used can come off, and then you can clean the plastic on top of the circuitry more vigorously (let dry completely before putting it back on)
Awesome work, and thank you for sharing the process! I like collecting these off-brand MP3 players from years ago, and there’s just not that much information on how to do these upgrades/fixes these days.
I’ve got a NOMAD Zen Xtra but haven’t done much with it yet. The battery’s borked and I haven’t worked out an easy work flow for getting stuff on it just yet. One day…