Side pull calliper brakes?
While reading some of the build threads here, I noticed that when a bike only has a coaster break, it's usually recommended that they retrofit a center pull v-brake (which because most cruisers don't have the proper threaded posts, a special plate has to be added). I remember back when I was younger that most of my bikes had side pull calliper brakes, and when I did a quick search I found side pull calliper brake kits for sale. As I recall, to mount them all you need is a hole on the frames centerline above the wheel which most cruisers already have for mounting fenders. Why not use these instead?