Via the screw.
yes
You wil have to call S&W with the specifics of your 629
You can get a owner's manual for free at the S&W website
If you go to Smith and Wesson,s sight they should have a service booklet that was issued with this handgun showing proper dis assembly and cleaning procedures.
HIghly recommend you leave this to a gunmsith.
Send it to S&W or find a gunsmith.
Best left to a gunsmith
A shotgun made for Smith and Wesson, sold under the Smith and Wesson name.
It's rather easy but be careful. You need to remove the rear sight to get to the release {http://i49.photobucket.com/albums/f292/YukonGlocker/MP9/fps.jpg} by putting the slide in a block and tapping the sight out. Wish it was more like a 1911, but good luck. John
Loosen the grip screws.
Take it to a gunsmith