Using Solidworks 2013 SP 2.0

I am building a thermal study to estimate the impact of using different types of thermal pads in an assembly. The jist of the assmbly goes: PCB->Thermal Pad->Heatsink->Wedgelock->Chassis

I am looking at how to handle modeling the DSCC 89024-07CT wedge retainer (see picture). It is a 5 piece wedge retainer with a 4.5" mounting interface and fastened to the heatsink using 2x#2-56 screws. The assmbly has many cards, and 2x as many wedgelocks. It seems over complicated to model the wedgelock in an engaged position and specify all the small thermal interfaces.

Is there a simple way to make the connection from heatsink to chassis without modeling the wedgelock in detail? Should I just specify a thermal resistace between the heatsink and chassis interfaces? Any suggestions on a good appoximation?

Thanks!