This kit is out of stock, and we won't restock it, but let us advise you on lighting up your UHK 60 v1.
You'll need T-1 (3mm) LEDs, the same type for all keys. If you use different types, color/brightness will likely be uneven. Make sure to get LEDs without a flange. (The flange is a tiny, circular rim that encircles the bottom part of the LED's lens, right where the lens meets the base of the LED. This rim is slightly wider than the rest of the LED body, sticking out and not allowing the LEDs to sit flush with the key switch, resulting in increased height and the inability to press the keycaps fully.)
As for the keycaps, although there are compatible keycap sets, we don't know any backlight-friendly keycap set with south-facing symbols. But even if the keycaps are not backlight-friendly, the illumination between them can be satisfying to watch.
Original product text: If you can solder, you can add backlight to your UHK 60 v1 with this kit, which contains LEDs, backlight-friendly, laser-etched ABS keycaps, and a keycap puller. The kit contains keycaps for both ANSI and ISO UHKs, and it doesn't contain Mac and Windows keys, only Super keys.
See the installation instructions.