"Conviction immediately removes the defendant from office. Following conviction, the Senate may vote to further punish the individual by barring him or her from holding future federal office, elected or appointed. As the threshold for disqualification is not explicitly mentioned in the Constitution, the Senate has taken the position that disqualification votes only require a simple majority rather than a two-thirds supermajority. The Senate has used disqualification sparingly, as only three individuals have been disqualified from holding future office.
Conviction does not extend to further punishment, for example, loss of pension. After conviction by the Senate, "the Party convicted shall nevertheless be liable and subject to Indictment, Trial, Judgment and Punishment, according to Law" in the regular federal or state courts. However, the Former Presidents Act of 1958, which provides a pension, and other benefits, does not extend to presidents who were removed from office following an impeachment conviction. Because of an amendment to that law made in 2013, a former president who has been removed from office due to impeachment and conviction is still guaranteed lifetime Secret Service protection. " wiki
IMO impeachment from federal office exists for the purpose of removal from office. A former official cannot be "removed from office." IMO the Belknap case will be treated as freakish. pl