Okay, I picked up some 2.0 plenums for spare parts. I disassembled them and found some differences. I am assuming one is late and the other is early 2.0. Both were said to come from 73 cars however. Notice the difference of the vent hoses. One has 2 large holes and had a double stacked elbow. The other one has a small vacumn hose size hole and a single elbow. The thermotime switch mounts are different for each. The throttle cable mount on one has two holes on each side for springs and the other only has one. Has anybody else seen this? Which one is the real 73 one?

The left one with the two larger ports is the correct one for '73-'74 at least. I have heard the '76 cars had the smaller port version, do not know what is correct for 1975 cars.

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I have corrected my spelling.

73-74 on the left
75-76 on the right