Not really possible installing grills and getting the shelter to fit.
Jim
HS..
You don't need grills in the F6B application and definately not extra grills. You have them with the oem speaker covers on the shelter. Neither affect your sound, measurably by ear.. Keep it simple.
4 Wheels Move the Body
2 Wheels Move the Soul
In Loving Memory of My Brother
"Death Waits In The Dark"