[Scorch]

They are drop-ins. Easy as pie: take the barreled action out of the stock, remove the bolt, clamp the action in a vise, drive out the two pins that hold the trigger into the action, remove the old trigger, open the package the trigger came in, read the instructions, take out the new trigger and poke around on it until you're ready to install it, then place it in the slot in the action, drive the pins back in, install the bolt, test the trigger, return the barreled action to the stock, go shooting. Pretty straightforward!