You will need plastic sail track to attach the Jayco Storm Covers to your Hard Lid Expanda. 

The dimensions required for one end are here: 

• One piece of - 2000mm sail track (Long Side)
• Two pieces of - 925mm cuts of sail track (Short Sides)

However please note: For the new 2016+ Model Expanda the longer 200mm piece should be cut into 1x 1100mm pieces and 2x 326mm pieces. This allows for a gap where the locking mechanisms are.

What you need: 

• White plastic sail track
• 8mm internal diameter standard sail track to fit a 6mm spline

https://www.campsmart.net.au/white-plastic-sail-track-2-x-2m-lengths

https://www.campsmart.net.au/jayco-expanda-storm-covers-front-rear-pack