cmittle; Your idea will work but it has a potential problem. The wedge has to bend the other part to spread it so when you loosen things it does not loosen completely so it is difficult to extract. I made some fittings almost identical to your design and discovered this the hard way. An alternate system is to just have matching flat angles on the two pieces so they get pushed sideways against the side of the hole when the bolt is tightened. When the bolt is loosened and tapped down everything becomes loose. If this description is not clear enough I can get some pictures.
An open mind is a virtue...so long as all the common sense has not leaked out.