Better yet, if the boot has been cracked for any length of time, just replace the whole CV with an Autozone etc, one. It will probably fail soon anyway and it's less messy!

You'll have to take off the inner boot to get the outer one, watch all of the CV inners, so that they go back in the same way, clean all the old grease, regrease with new, do both boots---save the hassle!