Excise duty at time of removal of goods

HI

As per the decision held in "CCEX VS MEHTA & CO ", The furniture and fixtures manufactionered at customer's site is movableand liable to excise duty.

Now the question is that as the furniture is built in the customer place itself and readied, there is no removal of goods from factory site (assessee site), so then when is it deemed the removal happnes and which date would be considred as removal of goods, in order to use the provisions under Central Excise Tarriff Acti 1985.