All the component designations stayed the same between the SMT version and the thru-hole version, that was by design. So, R5 is the correct resistor to remove on either version, the amplitude adjustment mod works exactly the same way for either.
All I did to do the kit version was take the SMT version and convert all the surface mount components to thru-hole. For various reasons, the components aren't in the same locations on the PCB, but that doesn't affect what you're trying to do.
