I talked to Brad at Rocky Hinge, and he also said that those back bolts are left loose, but his reason was to allow alignment of the back plate with the bolt holes!! I've learned my lesson on those two bolts, and they will not be ignored again. On the Right Stuff, my concern is that they say that all bolts are to be at final torque within five minutes, and that's going to be a challenge with this front drive unit, getting all of the pieces, parts and spacers in the right places, and then getting everything tight in order. It's all apart now, but I had to pull the radiator to get access - simply too tight to get everything out!