Hi All,New guy looking at sling options for a 590 SP Tac.light forend. I found what looks to be a good option on CTD as a tube cap add on,but I'm concerned about added thickenss disabeling my M9 from mounting. On the back of the bayonet mount,their is concern of too much interference with the light.. I got a good deal on a used never fired incase it crosses anyones mind how I found myself in this place!! Sugestions would be appreciated.