I installed these:
High Power 5630 Chip LED T10 921 License Plate Interior SMD Light Bulbs White | eBay
It was fairly easy (some hand and arm flexibility required, and I have skinny arms which helped, lol), and they work great. I got white LEDs, but you can get amber too.
When you're installing them, make a mental note, by feeling with your hand, of which way the lighting assembly is oriented before you remove them. In my car, VIN 2596, the assemblies were protruding towards the rear of the car, on both the driver and passenger sides.
Also, the cavity where the lighting assembly is is different on each side of the car (again, I have an early model VIN 2596). On the passenger side, the cavity was mostly empty, and it was easy for me to fit my hand inside and pull the assembly out. On the passenger side, there was some fluid tank there, probably the washer fluid tank. The cable going to the lighting assembly was also attached to the tank with some kind of clip. So there was less room for my arm and I couldn't pull the assembly completely out of the car because of the clip. It might have been possible to remove the cable from the clip, but I couldn't see it. I could only feel it. And after trying a few times, I couldn't get it, and I didn't want to damage it obviously, so I left it there. Instead, I stuck both my hands in to replace the bulb, which was kind of difficult, but it worked.