Zerodown mentioned: Did you transpire to have any challenges putting the forearm on with the Knoxx stock? When I put it on my 500a, the forearm was an complete bitch for getting on. Couldn't even place the nut back again on as there isn't any area. Interested to check out https://highimpactrounds.com/product/mossberg-590a1-spx-12-ga-20in-8rd/