According to Joe Baugher database, 1545 was originally built as a B-57B, sent to MASDC on October 30, 1969. Later converted to EB-57B. Sent back to MASDC on December 2, 1981. Still there as of January 15, 2008.
This B-57B began life as a "D" model bomber and was delivered to the Air Force on March 29, 1955. After storage at the "boneyard" at Davis-Monthan AFB, AZ, from 1969-1972, it was converted in 1973 to an EB-57B and flew until 1981.