There's nothing on the outside holding it on. So I opened the round plate on the back & tried to see. I can't see way up there so, I tried to feel it! Those same 2 holes that are on your machine are under that bracket...at either end. But there's nothing there holding it either. Directly under my spool pin there's a deep indentation inside...about 1/2" across. Maybe the spool pin itself is holding it down. PLUS, the oil hole on the right side of the bracket kinda curves into the oil hole. I'm guessing that the spool pin holds it down & the way the hole in the bracket curves into the oil hole keeps it in place. My spool pin is to tight to loosen to see for sure.