A lot of people were asking how to find the correct location for the rivet / screw holes. As long as you have a drill press you can use this method (mine is a cheap Ryobi). It's simple. 1)
Just turn the table sideways and use a level to check that it's uh... level. 2)
Use a C-clamp to hold the trunnion to the table. Make sure the C-clamp goes over the part of the trunnion where the recoil spring locks in, in other words, the part that the receiver doesn't cover.3)
Line the trunnion holes up with the drill bit and make sure the bit travels all the way through. Check to see that there's no pressure on the drill bit that it's not touching any sides. (Use a bit smaller than the actual hole size, but pretty close)4)
Slide the receiver onto the trunnion carefully so as not to move anything out of alignment. 5)
Use a second C-clamp to squeeze the receiver slightly so the drill bit doesn't spread it out when pressure is applied.6)
Slowly start drilling and let the bit pass all the way through one side and out the other, making sure the second C-clamp is keeping the receiver from spreading as the bit pushes on the other side.7)
Now you can use a hand drill to open the holes to the right size, then clean them up.
The same method can be used for the front trunnion. This is just a simple fool-proof way to do it. It's my preferred method since taking measurements makes my head hurt.