How many hours are on the motor? If not too many? You can re-ring/rebuild withour the worry of a ridge at the top.
If you are serious at all, you want new high compression pistons, and/or longer rods.
I have heard of .250" oe more being taken off a deere head, but the more you remove, the weaker the head gets. You may find your pushrods get too long as well.