Surefire fore end is the best option if you don't mind the cost.
Really if you NEED low light performance cost should NOT be a factor.
If it's just for fun then yeah, strap on a cheap light via mount and screw it into the hand guard of your choice.
Don't attach anything to the pump. Having your light moving back and forth sucks when you're trying to maintain a sight picture in the dark.
Get this simple device for $15. It attaches easily to the end of your mag-tube. You can then attach any picatinny light you wish.
http://www.alflahertys.com/collecti...ts/ncstar-1-shotgun-magazine-tube-mount-mt12g




























