[QUOTE=disaster999;15353868]It wouldnt go in at all. I chamfered the edges a little with a diamond file just enough so I can squeeze that piece on by hand and used a clamp to force it in the rest of the way. It was SUPER tight but somehow manged. I guess somehow that piece of carbon swelled up a little during the transport[/QUOTE
As long as you got it on there, you should be ok. However, one tip, if the arm is too thick, you should be able to lap the whole thing on some 600 grit and then finish with some 1200-2000 wet sand to get smooth finish to get the arm down to the thickness needed. I am not going to say this is the reason for matte finish arm, but it is an advantage that it is this way.
I have never heard of carbon swelling, but it could be quite possible that some tolerances are slightly different on the older production of shock mounts and across the A-Arms. Get some material that is 0.1mm thicker and a mount that is 0.1mm narrower, and there can be some issues sometimes.( 0.1mm on all items is standard high-quality tolerance in our industry). I have some on my car and they were a bit tighter than the newest batch ones, but they still slide on.
Regardless, if the items you feel are bad, send them back and I will issue replacements so long as they have not been damaged.