How to make Extang Solid Fold rear clamps even more secure?

Just put a new Solid Fold 2.0 on my 2015DCSB and I really like the look and fit.
I've got the rear spring clamps tightened all the way and I can still lift up the rear about 2" when the tailgate is up and locked.
One of the reasons I bought this cover was the extra security it provided for bed contents when travelling etc.
Does anyone have any solutions that keep the rear of this cover from being lifted even a little when latched?

 

You could install a hook to the cover and run a chain/cable down to the bed d-ring. Cut the cable so it has just enough slack to clamp on but not to lift the cover.

 

Yeah I've got some ideas but I'm hoping someone has already done something that works I can shamelessly copy

 

McMaster Carr has many spring sizes etc for sale. Might be able to get shorter stronger springs and use something to take up the slack with the shorter springs.

I got a Fold a Cover Elite, it's solid, no springs. Unless the thieves must get in there, they can still pry and break stuff with any cover.

 

I ordered another set of the same clamps as the front and it is now secure.

Only disadvantage is you would have to remove them prior to being able to fold up the cover, which is fine with me..

I'll post pics later today.

 

I thought about this but found a way to tighten the original clamps- I used a 3/4" nylon spacer between the nut and the spring. I also bought a cheap 10mm deep socket and ratchet and keep it in the truck.
I have the rear clamps pretty tight but I can still remove them. When I want I can tighten them up and it's much more secure now.