2) apply the black rtv sealant to the cracks
3) let dry 24 hours
4) spray the boots with WD-40 after 24 hours and twice a year or every
6,000 miles to help keep them from cracking. He also said not to use Armoral or similar products because that makes them crack. He also said to check for more cracks every once in a while.
I think this might work since the boots are not that old and the cracks do not go all the way through.
--Just trying to be helpful--