fastest way to right shift an array of 4 bytes

Using Arduino Programming Questions
2

I'm not fully understanding, if you right shift 32 bits from a size of 4 bytes, you have nothing left, all bits are shifted out.
Just clear the array.

Post the code you have.

EDIT: are you saying that code like this isn't working how you expect

long l_Data = 0x00FF0000;
l_Data = l_Data >> 8;