Here is a list of all Allied Me262 kill claims. There are 4 P51 claims on the 19Mar1945 but nothing on the 18Mar1945.
Sources:
USAAF (European Theater) Credits for the Destruction of Enemy Aircraft in Air-to-Air Combat, World War 2, Victory List No. 5, Frank J. Olynyk, May 1987.
USAAF (Mediterranean Theater) Credits for the Destruction of Enemy Aircraft in Air-to-Air Combat, World War 2, Victory List No. 6, Frank J. Olynyk, June 1987.
USAF Historical Study No. 85, USAF Credits for the Destruction of Enemy Aircraft, World War II, Albert F. Simpson Historical Research Center, 1978.
Combat Squadrons of the Air Force, World War II, edited by Maurer Maurer, 1969. Air Force Combat Units of World War II, edited by Maurer Maurer, 1983.
Compiled by:
Patsy Robertson, Historian
Organizational Histories Division, Air Force Historical Research Agency March 2010