It took about 8 months, I think. (I had had an orgasm while dreaming at 3 weeks post-op and a few times since then, so the frustrating thing was that I knew it was possible/the electricity worked!) The main issue was figuring out how the new bits worked - it'd feel nice and all, but not really go anywhere. Eventually I tried the Hitachi magic wand vibrator, and that did get me over the edge once, but was often too much stimulation and I just went numb. It was really annoying how what I needed kept changing, and I think part of what I had to adjust to was exactly that; in the old days it was basically one sort of stimulation, just faster and harder as I got closer. With the new parts I'd like gentle one minute and rougher the next, touch this precise spot this time but next time it'd be like poking my nose, and so on. And since I didn't really know what to do with the feedback (did that jolt mean it was good, or too much, or...?) it took me a while and some experience to calibrate the sensations enough to figure out what would work. Oh, and it had to be partly mental now, no way to get over the top purely by rubbing away down there.
Oddly enough, the biggest problem I had once I got past all that was the similarity of the motion sometimes to what I'd done before - it's gotten easier as the years passed, but at first if it reminded me too much the dysphoria would trigger and I'd be done for the day.