I am a collector that does not trust figures that do not use a stand, and I recently got some misformed metal cradles with some bases. I tired boiling water and clamping them to re-shape them and close them up, with no success.
Anyone changed the metal on a display base before?
If the top is merely too wide to position under the crotch, (which I often encounter), you can just grab the tops one at a time and strongly over twist them the wrong way. They will then bend back a little into the correct area but not be too wide.