I have got several questions regarding the wire I use to connect the components:
First of all – The exact diameter of the wire is not critical. Any conductive wire will do.
After lots of testing I think that 0.3mm diameter is the goldilocks option, not too stiff, and not too fragile.
I have used strands of wire from 1.5mm RK cable (24 strands in each cable) since it can be bought in any hardware store at very low cost. The RK cable is typically used as internal wiring in fuse boxes and control units, since it is easier to bend than the cables used in the walls (with single or fewer strands that are thicker).