how to modify our code for second mpu-6050.( which section(s) of program do I n)

Hi there,
I’m currently working on a project related to MPU-6050, arduino, and labview software for simulation. I have poor knowledge in C or C++ PROGRAMMING. I need to use 2 mpu-6050 sensors to capture the movement of human arm. I have downloaded one library for both arduino and labview and it is working great. the arduino library retrieve the raw values from MPU-6050, then convert them to meaningful data (3 axes accel, 3 axes gyroscope), and finally it filters the data by both complementary and Kalman filters. the result is awesome but…
the problem: I need to add another mpu-6050 to arduino, I know how the connection will be for the second sensor and i know how to use the address 68 for one and 69 for second imu. but the problem is i dont know which section(s) of program i should modify.
Note: the arduino library that I attach to this post looks huge but i believe that if anyone has experience with programming can easily understand which sections must be modified.
I’m completely confused while i was checking this library.
to those who recommend to use i2cdev library: i have used this library and it was awesome but i need to filter the data by either Klaman or complementy as well and that is really hard to implement in labview for me.
I appreciate your helps.

IMU_6050.ino (42.6 KB)