take care of fast soldering pins of switch - necessary because plastic is fragile and easy to melt
if you have helper solder flux ( usually used for smd etc.) or calophone, use that to ease/make soldering faster
In other words, get rid of RK27 circuit board, tie all grounds together, and run separate leads for inputs/outputs. Color coding helps you along as well. For example, make all ground leads black, all right signal leads red, and all left signal leads blue.
