I am left handed and tired of shooting right handed! I got a lefty bolt rifle out of storage and it seemed odd at first and I say this is crazy. I want to build a ar for me and I got to thinking. I want a slick sided upper. No coleman lamp pump, no door or lid on the side, and maybe close the little hole at back. Now with that type receiver can I cut a slot on left side for a handle attached to bolt and not jeopardize the strength of the upper? I really don't care about the looks or what folk may think that see it. I want a left handed ar.