I just picked up a new LCP custom with the red trigger and brought it home and noticed this as I was cleaning it.  My picture sucks, but inside the frame on the aluminum chassis on the right and left side is a line going up about 45 degree and I'm not sure if it's machining or a crack.  The wooden stick in the pic shows what direction it is going.  I couldn't get a good enough pic of it with my phone.  I can run the tip of the wooden stick over the line and feel a slight ledge as if the metal on the top of the line is higher than the bottom.  Maybe it my OCD

Mods you can delete this thread.

wow no one knows

J/K.  I went back to the gun store I bought it at and three other ones had the same marks.  It was machining so everyone can quit worrying now