As far as I can tell, the processes for the bog standard repairs are going to be nigh identical between the two. The board layout is extremely similar, all the connectors are in the same place. Processes may be EXACTLY the same, but I don't have an 8 on hand and I cannot seem to find any specific pictures of the iPad 8 internal layout. But I would expect it to be a translatable experience from one to the other. Even iPad 6 to iPad 7 is very very similar, aside from a few quirks and the obvious change is display size.