Depends on what you're starting with, and which crank they're going on. If the rods you're starting with are wider than the crank journal (i.e., wide journal rods going on narrow journal crank, SBC rods going on Buick crank ground to SBC rod diameter) you can narrow them on one side to achieve the offset. I did this with a set of SBC Carrillos recently.
If the rods are already the correct width for the journal, you can narrow the pin end on one side and run them that way. Take a look at this thread for more info on this method: