(a) Nothing contained in this chapter shall be construed as authorizing any departure from, or variation of, the express terms or limitations set forth in any will, agreement, court order or other instrument creating or defining the fiduciary's duties and powers.
(b) The terms “legal investment” or “authorized investment” or words of similar import, as used in any instrument specified in subsection (a) of this section, shall be taken to mean any investment which is permitted by the terms of section 1002 of this title.