Man...make yourself an offset ring and hang some 6x9s in there. You can use the template that comes with the speakers to build the ring. You can just cut it out of plywood and cover it with the same carpeting material that would cover a subwoofer box, or you can build a really spiffy one out of machined aluminium like KevinC did.

You'll need some long machine screws to mount it all up.

That's what's in mine - with about a 3/4" offset. I'm working on my thirds set of speakers and still using the same offset rings. I did remove a little door metal for the most recent set, but they're Alpine speakers and the magnets are massive.

Holler back if you need more.