President-elect Donald Trump is moving quickly to install loyalists and allies in his administration. But he is struggling to make a decision on one of his top law enforcement positions: attorney general, multiple sources told ABC News.

Trump interviewed several candidates for attorney general on Tuesday but came away unsatisfied, sources with knowledge of those conversations told ABC News.

Trump interviewed Missouri Attorney General Andrew Bailey on Monday and met with attorneys Jay Clayton and Bob Giuffra about the post, sources said. No final decision has been made, sources said.

In particular, billionaire Elon Musk was involved and participated in interviews with potential attorney general candidates, the sources said.

In a sign of how quickly other positions are moving, Pete Hegseth — the Fox News host selected as the nominee for defense secretary — was just called on Monday and interviewed for the job on Tuesday, a source familiar with ABC News told ABC News.

Within hours, Trump made his choice, sources added. Several Republicans on Capitol Hill and even some Trump allies described being “caught off guard” by the choice.

-Katherine Faulders, Will Steakin, Rachel Scott, John Santucci