Hi,
I noticed all the problems chalk river mentioned in his post. I attended one of Hungry's clinics and all of these isues were corrected. I added a USGI flash supressor and an new rear Springifeld sight- both of which I got on the EE and we swapped gas cylynder locks until everyone has one that fit- I think only a couple of people needed shims The most difficult thing about these upgrades was watching another guy at the clinic knock off my flash supressor with a hammer and a Giant Chisel.
The clinic was by far the best money I've spend- If you shoot a M14 your really have to attend.