How do i add music to the game

i couldnt find any method
i have a wav file i can convert it to rsd but how do i get it into the game?

i want to put a replace the sunday drive rsd with a music file which is rsd but keep getting invalid signature

It's not as simple as that, some hex editing is required. There's some older threads I can't seem to find with instructions.

Heres a video showing how to do it.