They bolt straight in, but if you feel the performance is pretty dull afterwards you will have to sort out the weights and springs under the base plate. There's a writeup here-
https://www.rollaclub.com/board/topic/42407-the-girls-ke70/page/4/#comments
and sorting out the springs is here-
https://www.rollaclub.com/board/topic/49927-how-to-fix-your-brand-new-ke-motorsport-electronic-distributor/#comment-511594
Overall, its a great idea and much more reliable over time.