Question about various rear ends

Here's a couple articles on the 8 3/4". One's a good comparison and the other digs a little deeper. Yes the main reason to switch to the 4 1/2" BC is that the selection of wheels is 100 times better than the 4" nowadays.

http://www.moparts.org/Tech/Archive/axle/1.html

http://www.moparts.org/Tech/Archive/axle/21.html