i believe solid is correct, if you have downloaded the lon config files, and car parameter/io files, you should be able to install the new cpu and upload saved files and be back in service, without ever having to use a lon adapter. hopefully the new cpu will come with the correct generic software. if not, then you would have to upload new software.
I have never had to just replace the cpu only in a running tac 20 with lon, so I'm not 100 percent sure that i am correct. I have built a tac 20 tester from scratch and added software,config files, then used lon adapter to program new ln boards. maybe i will try to just remove the cpu and put in a new one and see if the ln boards will still work with just the cpu replaced. any thyssen guys have the absolute answer? thanks