Not sure if anyone has chimed in with this, but it helps to use a punch or a rod that will fit through the hole to line up the trigger with the spring to insert the pin.
The MAC-11 net link will not be helpful for this situation, the M11 and M10 have a totally different trigger spring, with the M10 trigger spring being way more of a pain in the ass to install than the M11. You have to position the spring onto the trigger before installing it into the gun, then when you start to push the trigger through the frame into position, you will feel the tension of the spring pushing against the floor of the receiver, this makes it difficult to line up the pin when you go to slide it through the trigger spring holes and through the trigger to the other side of the frame. The tension of the spring gives the trigger assembly a tendency to tilt and the pins will not align with the holes.
The trick is to take a metal rod/punch whatever and shove it through to get the trigger lined up with the spring and the holes, then punch the pin through and push the rod out with the pin.. the rod will keep everything lined up. This makes it a lot easier.
By the way, the LAGE pdf attached isn’t helpful either, it shows the wrong parts at the bottom, it shows M11 parts, with an M11 spring. It isn’t gonna help you figure out how to install the M10 trigger with an M-10 trigger spring.
Your best bet is to look at the photos that the other user posted of the M10 trigger assembly, with the spring installed.. so you can get proper orientation of the spring.
Then do the trick that I just mentioned, use a narrow metal rod to line everything up and then slide the pin through using the rod to keep everything lined up and use the pin to push out the rod.