The Cataclysm DDA Wiki is your friend… Its information on installing seem to be accurate and up to date.
Someone included even the information about the failiure side of things (but without listing the limit if you don’t want to risk to fail extremly badly; which would be 29% (if my calculations from a long time ago can still be applied)).
Edit: In case the wiki goes down…:
Installing bionics is based off intelligence and various skills. The most important skill is First Aid, followed by Computers and Electronics. For the best chances of operation success, raise those skills as high as you can, and also make sure as much as possible that no penalty is decreasing your intelligence.