Trustees of a public charitable Trust amending the Trust deed to empower the sale of the property

It is a public charitable trust in Karnataka established through a registered document by the settler with some immovable property .The trust deed was not having any specific provisions empowering the trustees to amend the deed and also to make any sale of Trust property. However the trust is authorized to acquire property by way of purchase ,gift etc. After the demise of the settler , the trustees with the prior approval of IT department , amended the deed through a registered document incorporating a provision which empowers the trustees to sell the property as an amendment to the administrative clauses. With regard to certain amendments suggested to the object clauses the trust was advised by the IT Department to carry out the same through a Civil court. Q.1 - Are the Trustees empowered to make amendments to the deed when there is no specific provision in the original deed which empowers them to make amendments ? Is it a valid amendment? Q.2 - Can the trustees sell the trust property by virtue of the amendment ,with out seeking permission of the court and that too through private negotiation?