The KV6 was derived originally from the K series, although they really have nothing in common.
Doing the thermostat is not a disaster, its even possible to replace it without removing the manifolds.
Here is the thermostat with 2 of its outlets showing...
But unless you have seen the offending pipes its going to be difficult to know exactly what is required.
I'.also unsure on the insistance on "silicone" pipe, there are no slicone pipes fitted to the engine.