Usually the only differences I find between columns of different divisions of GM is the style of the turn signal/tilt stalk, different style knobs on different columns. The stalks interchange, so its easy to switch to make the column correct if you want to. Also if there are wiring differences it usually is only the style of the plastic connector at the wiring connection. Again, if needed the wires can be popped out and installed in the correct plastic connector.
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70 chevelle ss396 conv
66 chevelle ss396 hdp/conv
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