The way that I do my pivot pins maybe different than many others but here goes. I will make the hole in the blades .001 to .002 larger than the pin dia. I pick a pin that is as close to the bolster hole size as i can find. I do not have a little lathe yet so I purchase my pin stock and it varies quite a bit in size. I like to think as I peen the pin it swells up and grabs ahold of the bolster but does not swell and lets the blade pivot. As far as how much longer the pin is , I guess I am about .030 proud of the bolster when I start to peen. As I peen I look at how I am filling the counter sink and I may take the knife over to the belt sander and reduce the height. I do not want the pin to crack radially. I also have some heat treat foil in between the blade and bolster and as I peen I keep checking the blade tightness . I peen till I feel the blade getting a bit tight then pull the shims out. At this point hopefully I have filled the counter sink and will peen to get any side play out. IF all goes well , when I grind down the proud part of the pin, you can no longer see it.
Ken