Motor mount differences?

[PA Dodger]

I recently bought a '69 Dart that had the engine replaced before I bought it. It was a 273 and is now a 340. I noticed the TTI headers rattle off the torsion bar on the pass side and the steering box on the driver's side. The headers haven't been beat to death for clearance. I also see a few washers under each motor mount rubber isolator to space the engine up. The rubber isolators don't sit under the motor mounts the entire way. They stick out in front of the bracket a about 1/2".
Could the motor mounts for a 273 bolt up to a 340? Is there anything else I should look at to correct this problem?
Thanks
Dan

 

[Rocky_JS]

my 67 273 does the same thing, the left 340 engine bracket is different than the 273 one. the 340 is about 1/2 more narrow. so if they did use the 273 mount it would have spacers or washers etc on one side of the left mount bracket.