Before you come on here and discredit a member, and tell him he is wrong, have some proof of what you speak.Here is mine.
First pic: 273/318 right (passenger side mount). Bolts up to the 360 no problem.
Second pic: 340 A-body left (drivers side mount). Bolts up to the 360 no problem.
Third pic: 273/318 left (drivers side mount). We have a problem.
So untill you can show me anything different,your information is incorrect.