Alan Dershowitz has said that Kavanaugh can only be impeached for acts conducted while on the Supreme Court, not prior acts to that position (same for Trump - only for acts as President, not prior). Then again, the Dems don’t care about the law and impeachment is ‘political’ so I imagine they’ll try to go after him on whatever grounds they want. It ‘should’ be a major waste of time/energy and as you said, I don’t think either will be removed from office. If the Dems go after impeachment charges, they will continue to demonstrate that they are the equivalent of turd-throwing baboons.