I actually did some calling around yesterday.
Hood racks: On a private vehicle, you need to get approval from license office.Take notes Raj
The sound itself : There's apparently a mike man association that has the forms in order for you to operate.This is renewable at license office every three months.
Other than that you can be ticketed for violations.
Again, Raj take note.
This is what I got from a neighbor that works license office.I didn't find anything in the laws as yet