Gotcha.
k55v is done long before the 7,000 hertz cross to the tweeter in the chorus ii. Tweeter high pass should be lowered.
Stock chorus ii network relies on the natural rolloff of the k53 at it’s upper end. Unless the replacement mid has the same roll off, a bandpass will be needed for any driver that plays higher. Forte iii (k70) and forte iv (k702) drivers included. The horn itself is used to 20khz in some pro 2 way speakers.