DRV10983: Through whole package

We need to manufacture our driver PCBs in-house. Our capabilities can support traditional but not HDI PCBs. Do you have any suggestion?

Like for example, is there any mounting kit that can do the adaptation?

We do not recommend mounting kit because we recommend the IC thermal pad to be in contact with the PCB for thermal heat dissipation. Unfortunately, I do not have any other suggestions.  

So to use the PCB as the heat sink, is there a custom PCB design recommendation, I mean area, shape ....

I checked both designs and need to confirm a point: DRV10983 is using the GND plane to dissipate heat. Practically, I can implement the whole design in one PCB layer. However, from heat sinking point of view, do we need both sides GND planes to dissipate the heat? or one side is enough?

Board size is 50 x 60 mm