There is never a lack of butchers on this site. Did you ever ask yourself, "if they wanted them stretched before installing them, why they don't send them to you pre-stretched?" If you can't install them without destroying them, you may want to invest in one of these:
http://www.lockintool.com/
Fwiw, I am the farthest thing from a "butcher", and most people I know
and deal with claim that I'm too picky on alot of stuff. plus, I don't reuse
locks, and I also don't destroy them taking them out, also using the 2 pick
method. I didn't look at the link, but if it's the tool I think your talking about, you have to have a grove/slot machined in the piston to use it, beforehand. it doesn't work without it.