I've got an AMD-63. I measured the notch in the front trunnion that the bolt slides on it is mic's out at .280. On the ACE website, 762 used a letter "C" bit to space from the top rail down to the position of the lower rail. If the gap in the front trunnion is .280...top edge lines up with top rail, shouldn't the bit be something more like a "J" or "K"? I base all of my measurements and predictions off an AMD-63. I think he built an AMD-65. If there are differences in the trunnion, I could understand the differences in bit sizes. But if they're the same trunnion and I'm also using an ACE blank what's going on? Other observations would be greatly appreciated!