clamp together amp and effect rack

I have a guitar solid state head/amp unit and a normal sized effect rack that I want to be able to carry around together easily.

The amp is about the same size as the rack, except it doesn't have the bolt/screw section on either side, used typically to mount racks into cases. It sits nicely on top of the rack. I'll only be carrying it to practice and back at this stage, so doesn't need to pad/protect the units so much.

A typical four-sided case is out of the question the amp needs good air flow around the side and top panels.

My idea is to find two clamps - one for either side. I'm thinking something similar to a car battery clamp, but not sure that would work specifically as the ones I know of have the bend at the end of the vertical bars which would prevent me putting the units down flat. But the concept is good because it would provide maximum airflow, and be adjustable and easily removable.

Would really appreciate some ideas on something that would suit this purpose, or other solutions.