A local gunstore has a NIB Steyr M40 for $505. The serial no is 57xx (I forgot the last two digits). I will purchase it only if the ejection port has been modified. I called GSI and they said serial no 5700 had not been modified. I did not want to bother them to go thru 5701 to 5799. My question is by looking at the ejection port how can I tell if mod has been made? The front and right side has been cut at an angle (not 90 degrees maybe 45).I don't want to go thru the hassle and cost of sending it back.Thanks.