Thanx, didn't think that so much people like this that much.
the second prototype even has a third nacelle on top as the TOS klingon engineers thought this will make the ships faster but this attempt failed and only these two prototype configurations existed and it was mothballed after the K'Tinga entered service.
the second prototype was in fact the same ship but the engineers had mounted the third nacelle on top of the hangar housing.
However later in the time as the Fed Excelsior entered service the Klingons wanted again some kind of fast cruiser and the old plans of the K'Tkara where taken out again but the design that entered service had changed radically.
i have done the textures and finished the model for the second configuration.