Making it easy to find is not copyleft. And copyleft is a concept that doesn't exist in the concept of copyright.

Making something copyleft means I and you would have permission to make copies of the designs and the manual and make changes to them and sell a product based off of those designs. And that I would also require the same from my designs.

It's a license that encourages collaboration (I take someone else's work rather than reinvent the wheel, and if I improve it I share that improved design back with the world and let them do the same) rather than competition (where the original designer would sue me for using or improving their design)