340 Timing / CAM Issue

We just bought a 72 Dart "project car". We appreciate this forum and have used it a lot already. Sorry for the long post!

First some history as I know it. The motor was transplanted out of a 73. The car was originally a 6 cyl. The project was never finished by the person I bought it from and it was never on the road....maybe a lesson there..
Anyway, here is where we are...

73 340 block and heads from what I can tell
Mopar cam 4452782
Not sure about pistons. Here comp test results
Left front to back - 160-160-160-160
Right Front to back 175-160-160-140
Stock 4bbl manifold
Edelbrock Speed Demon 650

The engine starts but idles like it has a race cam in it.
won't idle below 1500 rpm and 30 degrees advanced.
5 inches of vacuum.

Here's what I have done.
Pulled the front end off and checked the timing gears and everything lines up.
With the marks lined up I pulled the dist cap it appeared that the rotor was 180 degrees off. Bingo! Rotated the distributor and put everything back together.

Would not start and back fired through the carb.

I pulled number one plug and did the finger in the hole till it blows test. Got it to TDC and pulled the cap...180 off!

Pulled the distributor and put it back to where it was and we are back to running but very poorly as described above.

I know my way around cars but this has me stumped. Could it be a wrong cam? Combination of parts? Am I going to have to tear it down?

Thanks for reading and responding!

Jack and Mike