Modify code to output PPM via Arduino pin insted of NRF24 Transmitter

Hey Friends,

I will be happy if you can help me modify code for my project.
My project goal is to output PPM (8 channels 22.5ms).
The inputs will be 4 Hall sensors (as Joystick) 2 switches (on/off)
And an external Head tracker which already output 2CH PPM (CH5/6)

I found this project code which is very close to my needs:
http://www.electronoobs.com/eng_arduino_tut25_code3.php

Is it possible to modify this code to receive 2 external ppm channels + the analog source
and output all as PPM without the NRF24 transmitter(I would like to output via mono cable).

would this thread be better off under gigs & collaboration?