A lot of the problems expressed here is alignment of holes for the hinges. I'm a builder and I have learned alot about hinge points and the centering jig that I don't use any more.I don't use points on 40 size planes or some 60 size because they were not intended for those planes in the first place. When building I take all trailing and leading edge feathers, in some cases each one will consist of one or more pieces and I glue the indivdual leading and trailing pieces together (straight) and stack and nail the pairs together with T pins. After they are shaped to their finished size a line is drawn down the center and hinge location marked they are drilled in drill press with proper size bit. Mark ends for identafacation and add them to your build parts. Are you starting to see where I'm going?.
In the end. you use those holes for guide to drill any blocks installed per plans Hense perfect alignment every time. and not only that you use dowles in them to put parts together to finish sanding your mateing parts for perfect fit all around and they can't be made better any other way. In the case of the build is done? just do your best and good luck
Leroy
Plenty here on the glueing.