Thank you Pete but I'm certainly no master. I just ripped off that idea from someone else, I don't remember who. Last year I spear-headed a uke building project with all of our guild members and now everyone here (almost), even some old traditionalists, have adopted it. I won't go into depth but there are a few reasons I like it.
I can bolt and unbolt the neck as many times as I want during construction ensuring my neck angle, body to neck plane, (no more 14th fret humps) and resulting action is exactly what I want it to be. It also allows me to finish the body and neck separately which is a huge advantage is achieving flawless mirror finishes. It has rocked my finishing world.
Aaron, I prepare the body/neck junction just as I would a bridge. The entire body is sprayed, then the neck area is scraped. What this does is creates a very small void where the lacquer was removed and allows the neck to be snugged up real tight. Although not really necessary I apply a drop of glue in the lower area where the heel cap is. The fret board extension is also glued and clamped.
I'm not saying that this is a better method of neck attachment, it just fits my style of building better.
Pete, those bolts are available through wood working catalogs. I've gotten them through Rockler but they are available at my local big box home improvement store as well. They are labelled "cross dowel bolts".