If you want to do it on isolated mito from mammalian tissues (which is not what we've done here, no isolation in our case!) it was already done ! You can check here www.nature.com/articles/s41... But it's still very challenging!

High-resolution in situ structures of mammalian respiratory supercomplexes - Nature

Mammalian respiratory supercomplexes are imaged in their native membrane environment by in situ cryo-electron microscopy, providing insight into their reactive intermediates and conformational dynamic...

Oh awesome!