MB007AM

Hey everyone on this forum pls provide some advice I know not all of you like the idea of tuning cars but some do so i could use some guidance or a reference point

i believe i have one cat left, the other is removed and i have no mufflers. If I were to remove the final cat, is there a video reference on how loud it would be? Car also has downpipes and is loud as it is

I heard there are cheap valve options that I could use so it could muffle some sound.