TJ, and others, here is a solution I learned from Randy Morin:
First thing I do with a new Great Northern quiver (and most others) is throw the foam it came with away. I replace it with a high density foam the local kyaker's use for additional flotation.
A piece 12"x12"x4" makes over a dozen foam inserts for less than $20 bucks ($15 for the last piece I bought 8 years ago).
It is, unlike the GN foam, quiet.
When I used the Grizzly 190's I left the foam 3/4" above the hood so none of the blades were exposed.
The foam usually lasts me 2-3 years with the broadheads completely imbeded, protecting both the broadheads and clumsy me.
I use a bandsaw to cut them out, but a serrated knife works just fine.
After getting the right fit, a little contact cement will hold them in place until they wear out.