I have the sides attached on all three of the new tenors now. Thought you might enjoy seeing how it is done
Here is my assembly jig with a top set on it ready to accept the sides.
First you carefully trim the ends of the bent sides and try them in the jig until they fit perfectly. Take your time here. It is really important. When the sides fit just right it is time to glue. It is helpful to tape the sawn butt ends tightly together in the position that they will be when complete
Now apply glue to the back the butt plate
And to the underside of the side where it will attach to the top. Smooth it all out with a brush
And now slip the sides into the slots in the neck and adjust the six jig "dogs" to hold the sides in the proper place. Then you can clamp the butt plate caul to the butt plate bringing the side joint right to the center line of the butt plate. Clamp it down tight, you want a good connection here.
Now with the ever handy Irwin clamps hold the side down tight to the top. Then with a few drops of glue and the brush go all around the side/top joint on the outside brushing glue into the joint, You always scrape off a little glue in the fitting process and you want to be sure that there is glue in the joint in its final position.
Now clean up any spilled glue. A neat way to pick up glue is to cut a plastic straw like this. You can scrape up excess glue and wipe it off the straw with a wet paper towel. Works like a charm and makes your work much neater. At this point I like to glue in a few of the tentelones where I have access. Now you can sit back and enjoy a beer, or play your ukulele. One of the really critical parts of your build is done. Let the glue dry for a couple of hours at least.