Be careful not to dislodge the bolt stop spring when disassembling the factory trigger unit from the action. Save yourself the time and a headache;)
A good way to deal with the bolt stop and spring: Get an 1/8" 'alignment' pin from the hardware store and use that to tap the pin out the the bolt stop and spring....that will keep everything in place. When the rear trigger pin goes back in, it will move your 'alignment pin' out. No fumbling with the spring or trying to get the pin hole in the bolt stop lined up as you go through the wound center part of the spring. The first time you do this, it's not a bad idea to work inside a clear plastic bag...keep everything contained.
It took longer to type this than to do it. ,)
Darrell Holland offers a reduced tension bolt stop spring that makes a nice difference, especially in cold weather on when you have gloves on.
Good shootin'
-Al