modular concrete mold project/problem

I have been trying to figure out how to tile four shapes in order to create a definition that will tell me how many units I will need to build a wall at a specific length and height.

I have modeled four shapes and have tried a number of methods of tiling (boxmorph with offset grid etc)

My initial thought was to divide a surface and then use boxmorph but I have not figured out how to overlap the boxes and to subtract every other one.

I have had trouble trying to pick every other point or box using dispatch or cull

Any help would be amazing!