I just came across some transcripts on the Miller Center website. The Miller Center, here, is transcribing and putting on the web presidential voice recordings. Us old timers will remember that President Nixon secretly recorded a number of Oval Office meetings and telephone calls, which ultimately contributed to his downfall. Among those transcribed are some referring to Johnnie Walters. Here is a link to a search on that site for Johnnie Walters, which picks up the material related to Johnnie.
I cut and paste below one of the offerings from these materials; the web page is here. The discussion appears to revolve around getting a more compliant Commissioner of Internal Revenue to replace Johnnie Walters who resisted the White House's political overtures:
President Nixon: The IRS thing is important but, God, we ought to be able to get some loyal son of a bitch.
H.R. "Bob" Haldeman: I think we can.
John Ehrlichman: We will, we will.
President Nixon: There ought to be some guy that will do our bidding. That’s what we want, isn’t it? I don’t want that to drop between the stools. I don’t want another Johnnie Walters. We’ll get some—OK. [Unclear] a guy on your own staff. How about [Egil "Bud"] Krogh? Is he a tax lawyer?