Hi Stephen,
So long as you do not have any perennial weeds e.g. dandelion roots and bind weed etc stack the clods grass side down in an out of the way place and in a years time you should be left with nice friable top soil you can put back on the garden. If the clods are wet when you stack them cover your stack with black plastic to prevent any grass that may want to grow. If the clods are dry when you stack them wet them and then cover.
Hope this helps
Happy gardening
Head Gardener