I know that this has been covered elsewhere using the G2 repair manual, and I tried this when I managed to borrow a green label G1 to check against my Silver label G1. The 2 cameras are similar serial numbers between 80000 and 81000, and 1 got the upgrade the other didn't. The sliver G1 has all sorts of focussing problems with the 90mm and sometimes with the 45mm. One thing that I noticed comparing the lens data between the 2 cameras, is that the table entries for the 45mm and 90mm lenses are different, it would seem that the green label upgrade did more than add support for the extra lenses, it appears to included a modification for the 90mm and 45mm lens support. I suspect the data that changed are motor commands, I have seen it claimed that some of the G1 left the factory with he wrong numbers set up in them, that caused the lens to be moved to the wrong place, and so the image to be out of focus, even in manual focus mode. I have managed to adjust the auto focus on the camera as well to set it to match the green label G1. Sadly there are enough differences between the 2 cameras for the method used for the G2 to not work on the G1 without some modifications. I suspect the differences in lens data may explain the whole the autofocus is terrible, no it is user error debate, as some of the cameras are set up incorrectly and will never work reliably with the 90mm and 45mm lens until the correct motor data is entered. This does however seem like it may be possible. I have noticed that the Green Label G1 performs a lot better than my Silver label one did. Is anyone interested in the results I get?.