Simulink for Observer-Based Control

I'm trying to build a simulink model for an inverted pendulum using an observer-based LQR controller. For details, you may refer to the following website (the observer-based controller section starts about half-way) Inverted Pendulum Model

As a summary, I have a model for the pendulum system:

x' = Ax + Bu where A is 4x4, B is 4x1
y  = Cx + Du where C is 2x4, D is the zero matrix

Moreover, the model for the estimator is

z' = (A-LC)z + Bu + Ly where L is a 4x2 matrix

I have been able to construct most of my Simulink model thus far (I defined my A matrix for the estimator as A-LC) with image attached. Note that u=-Kx represents the LQR controller.

I haven't been able to figure out how to add "Ly" into my estimator model. I have tried various ways unsuccessfully, hopefully someone is able to help, many thanks!