Motor mount bracket difference - 318, 340

Please help! Doing my first MOPAR project and noticed that the engine mount bracket, on the LH side, removed from my 1969 318, does not fit my 1969 340, which I plan to install in the car. The 318 motor has 2 bosses with 4 holes on each side, but the 340 has 2 bosses with only 3 holes on each side. The RH mount fit perfectly, but the LH does not. Where can I obtain a mounting bracket that will work? This is for a 1969 barracuda.
:banghead: