The WCT are of two types i.e.within Orissa and CST. If you carry all the required materials from Mumbai and do the installation only in Bhubaneshwar then it becomes an Interstate WCT.only CST is chargeable by you ,of course @ 2% against 'C' form from the buyer of machinery. If no'C' form full VAT of Maharashtra. In case of Interstate WCT the Orissa party should not deduct WCT TDS,because that money goes to the Odisha govt.That benifit will not be available in Maharashtra.So,you will be the loser of TDS amount.While adjusting the TDS payment to govt has to be verified.If you are buying some material in Bhubaneshwar for this installation and supply of machinery,then, you will have to register under Odisha VAT Act,submit returns,and adjust the TDS also.......mjk