Chosen Solution

I bought the MacBook Pro 15" Retina (Late 2013-Mid 2015, Dual Graphics) Heat Sink which just arrived today. Its supposed to have mounting bars that press it onto mother board. I didnt get that, not sure where i can get this.

Are you replacing an IG logic board with a DG board?

You should have gotten the heat sink with the logic board if not you’ll need to contact the seller of the board. Or order a new heat sink with the needed hardware as some sellers assume you are replacing like for like and you would already have the clips and screws 15” MacBook Pro Heatsink - Discrete Graphics, Apple P/N 076-1453