The P70 is not difficult to do, I have recently done a few 8002 S2 Anschutz, they are much more involved.
the is no blanket answer as each 10m rifle design will require different amounts of work. P70 is quite straight forward compared to some. Well as far as getting it to full uk power. You may want to modify the ergonomics of the rifle too but that is a personal thing to suit the user and its new use.
HFT, for people with only 2 buttucks!
VooDoo TwoTwo The next chapter.