You should be fine. I just installed mine last night. Do it like this:
Remove old stock-watch for the buffer detent pin & spring, the rear takedown pin spring, rear takedown pin, and the little retaining pin in its slot-all small pieces, easy to lose.
Put all those pieces back in, once you have removed the old buffer tube, and screw the new buffer tube in, making sure you dont crimp the rear takedown pin spring, and making sure that the lip of the buffer tube detent is below the edge of the buffer tube once its screwed in.
Lube the buffer tube-I used CLP, but I am sure anything would work-was gonna use olive oil, but I didnt want it smelling like a salad
Slip the ACE stock onto the tube, then the neoprene cover over the tube. Push the ACE stock all the way in, while slipping the cover on as you go. Should go on pretty easy with only a very light coat of oil.
Seat it in place, put the screws in, and you're good to go. All in all, its about a 5 minute install, unless you lose a spring....