Hi guys, I am here to ask if someone have made or if exist somewhere rules for random generating matrix systems for the Shadowrun 4th edition (I dont have the 5th edition)

I remember that in the 2nd edition there was rules for random generation of matrix nodes and paydata, but for some reason I dont find these kind of rules for the later 3rd and 4th edition books. I am missing something?

Any help is apreciated.