GST Opening Stock

My client is a powerloom owner, he don't have any vat tax liability. On 1st July he has Opening stock of finished cloth of Rs.4,20,000/-, don't have any yarn purchase in the month of july. Sale was Rs. 62,000/-. As there was no tax on his business before 1st july 2017, what will be the treatment in GSTR-1 as he is now liable to pay @5% on his purchase and sales. Does he claim any input tax credit or get any exemption on opening stock?