I'm one of the sickies here that doesn't think that clatter is noise, rather it's music.

For those who DO want to quieten it, the hood pad helps a little, but lead foil sandwiched between foam and lining the front floorboard and fire wall will do more than anything.

I used some of this stuff in a street rod that I built in the very early eighties and it was amazing. You have to place it smartly because obviously it is heavy, you don't want too much of it.

Good luck,