Hey Guys, I am finished! As described, the old MacBook Battery from the 2015 Modell works perfectly with my new Logic Board. The USB-C Flex doesn’t fits into the 2015 Topcase. With a multi-function tool, I had to remove a bit on the inside of the Topcase near the USB-C Port. Now the new USB-C Flex fits into the “old” Topcase but the Screws was to long. I have replaced it with two Screws from an old & broken iPad mini. Hold like out of the factory. The new Trackpad works (sure) perfectly. I don’t have tested the 2015 Trackpad.