Assuming this a small block ? the legs on the bracket are offset, one is taller than the other. BTW your local bone yard probably has some sitting on top of a motor in either a p/u or a van from the late 80's early 90's. Thats where I got mine !
I also have a 340, and the coil bracket I have has both legs the same length. Maybe it's from a B/RB motor?
Where can I pick up the correct coil bracket for a 340?