I will preface this by saying I work with metal for a living, but it was easy and took me 1 hour to fit a Wilson ambi to one of my guns. Half of that was lopping off the left side pedal to my liking, rebluing, and inletting the right side stock for the retaining tab to ride under. Did both of those tasks with a dremel tool.
I fitted the safety with only a DMT diamond file, a sharpie marker and patience. I installed it, felt where it started to bind when applying the safety, removed and looked at where the metal was marked and filed. Sharpie markered area black and repeated. When I was done I worked on the detents so the safety was more positive in staying off. Passed all safety checks.
I found it useful to work only installing the left side of the safety and also to remove the grip safety so yo could study how the parts interacted.