I ended up putting in a pair of yamaha 8" woofers. I took them out of my pair of NS-636. I made a whole new front panel. I really like they way they sound. Matched with a pair of Realistic horn tweeters.
I went this route because I picked up another pair of NS-836 for 15 bucks with stands. So now my surround system has 4 NS-836, which really like, I think the NS-836 are unrated with the right stands and placement they are really good for home theater.
My 2 channel system now consist with the Pioneer HPM 100s and the Utahs in the far corners for fill. They will probably make there way outside during backyard theater nights.