Regarding inverted refund

I'm contractor who buys some components to make a product and then I sell it.
means I'm doing business of solar street light. I buy components on higher rates and then I make a product and sell it on lower rate. problem is here that.. I buys goods from interstate and then also sell it in intrastate and Interstate.
With the definition of 54(3) sub clause 2 ..it is mentioned that no such refund can be claimed on IGST and CGST.
How I will take refund on this.