Due to the angles, space is the enemy. Due to the angles, the holes only line up when the doughnuts are pulled tight. Either tighten the bolts or use clamps. I think that I put the tops bolts in then used the engine weight to pull the bottom doughuts tight (with a bit of wiggling up force to align the holes) and used a taperred shaft to get hole in alignment and tap the bolt in from the other side.