Is the stock cracked you think? You should be able to tighten the stock screws without removing the trigger plate screw. Just remove the trigger guard and tighten the screw at the rear that goes through to the top strap and tighten the screw under the opening lever. You shouldn't have to remove that trigger plate unless you are wanting to take the stock right off. I bought a small 1/4" impact driver for removing stubborn screws. But you have to have the proper bit.
Edit--I checked mine. I see the trigger plate extends far enough that it covers the screw going through to the top strap. So, yep, the trigger plate has to come off.