Inside the Company p. 613:
"Joint telephone-tapping operation between Mexico City station and Mexican security service."
Philip Agee, Inside the Company, pp. 353-354:
technicians and LP operators...have an uncomfortable situation with the heat. Those tube-operated Revere recorders give off so much heat that the room is stifling in the summer." Although Agee was discussing Ecuador, the same equipment was used by LIENVOY. https://leaksource.files.wordpress.com/2014/08/inside-the-company-cia-diary-philip-agee.pdf Also see generally Bill Simpich, State Secret, Chapter 4.
"In August 1958 the US Ambassador, Robert C. Hill, entertained Carlos Trouyet (owner of the Mexican telephone company and Mexico's richest industrialist) at a breakfast where Winston M. Scott, COS, was invited. Scott was introduced as an "expert on Communism". Trouyet, an extremely pro-US Mexican, offered him assistance in collecting information on Communist activities...there were ten Mexican employees working in the listening post who prepared the daily transcripts and a summary of information from the lines that were not fully transcribed. This summary was delivered each morning about 0800 to the station case officer by AREHART. Any items of unusual significance were brought to the attention of the chief of station before 0900 hours."
1958-1961: "During 1958, Win Scott met socially some of the (cronies) of the Mexican president-elect, Adolfo Lopez Mateos. During this period, the US ambassador Robert C. Hill (reflecting the policy of then Sec State J F Dulles) was energetic in organizing groups to 'fight communism'. (This)... grew into a proposal Miguel Aleman (jr son of former Mexi president), acting for Lopez Mateos, made to Win Scott for a joint telephone tap operation. This project (LIENVOY) went through about four distressing years of a shakedown. The Mexican in control (LIELEGANT) was inexperienced, old, and greedy. His son (LIENVOY-2) was a masterpiece of deceit and corruption. LIELEGANT also manipulated control over the principal agent of LIBIGHT mail intercept. The first case officer was Alfonso Spera inside with Turner Smith (retired) outside and John REDACTED (TSD training officer for surveillance and head of the listening post where thirty telephone lines would connect as well as a transcription room staffed by Mexican army officers.) Initially the station tried to meet every demand made by the Mexicans. (Due to language problems and more...) the Mexicans were virtually uncontrollable, spending money as they pleased, squirreling away equipment at enormous costs, and neglecting their part of the bargain in the production of transcripts or placing taps which we wanted. Spera was replaced by Jack Brady who found himself in the same pincer movement of having Scott approve a request by LIELEGANT that Brady had turned down by his son, LIENVOY-2. Smith and John...were replaced by a TSD officer, Charles Flick, who was put inside the listening post to maintain the equipment...Scott took over the project as case officer meeting with LIELEGANT. He designated Ann Goodpasture to meet (daily) with Flick for routine supervision of the listening post...(generally Scott made the decisions)...This was about late 1961." 2/10/77 notes of Anne Goodpasture prepared for John Leader, IG Staff.
1/23/62 dispatch between COS Win Scott to C/WH J.C. King: Scott implictly admits that the transcript sent to LITEMPO-2 is fake. Refers to it as a "transcript" and that "it was felt it had to be supplied" because the Ambassador made a statement about the Cuban ambassador personally paying students. "No tape exists for this, and REDACTED will be told that it has been erased if he requests it."
6/15/62: Arnold Arehart/Charles Flick, the LIENVOY chief, recounts how he was surveilled near "the LP", describing what appears to be the LIENVOY listening post (LP) as near the corner of Tonela and Chihuahua in Mexico City. Another version is slightly more legible: https://www.archives.gov/files/research/jfk/releases/2018/104-10187-10030.pdf
"...the monthly operational report for Project LIENVOY activities during October 1963...Mexi-6453 reported a contact by an English-speaking man with the Soviet Embassy in Mexico City. This was forwarded to Headquarters for further dissemination."
11/27/63 cable DIR 85245 from HQ to Mexico City: "Pls note that Director (FBI) is getting from (FBI) MEXI (illegible) info that obviously originates from the LIENVOY operation. (Illegible) more apparently does not realize that this info was produced by a (CIA) operation, and indeed, (FBI) may be getting this LIENVOY info through its own clandestine sources in the Gobernacion office or even in the President's office. Please try to clarify with the (FBI) rep there the exact manner in which he has obtained such info and the form in which he has sent it to (FBI). We must avoid the inadvertent compromise of LIENVOY. Advise. End." Marginalia by Scott states that an answer was sent to whole cable, with copies to "liaison to (FBI)" and "LIENVOY/OPNS" (?)
12/3/63 - Lienvoy transcripts - "index Kihss". Reference to journalist Peter Kihss of the New York Times.
6/18/65, cable MEXI 3832 from COS Mexico City to C/WH: GPFLOOR-related tape transmitted.
1997: General counsel Jeremy Gunn writes a memo to John Pereira of the CIA's Historical Study Group stating that the ARRB believes that the Mexican government may have its own copy of the October 1, 1963 intercept of Oswald - uncertain whether it is a transcript or an actual tape.