I used these.
http://www.midwayusa.com/product/366...stud-115-b-set
You have to get the type with a nut to go on the forend. Drill a hole through the stock and attach the nut. I applied fingernail polish to keep the nut from working loose. You might need to shorten the screw to prevent it from touching the barrel.
The screw for the buttstock works just like a wood screw in the plastic.