It is doable but I usually look at what is going to be the best fit for the back of the quilt. Those 4" your are trimming off might just help you extra yardage you need for a backing. My next quilt might just be this quilt that needs black & white prints called Diamond Heads by Cozy Quilt shop:
http://www.ebay.com/itm/172010101311...%3AMEBIDX%3AIT