Help please, plug reading wizards!

K.O. SWINGER said

Good info one thing I see are four plugs that are a little rich but two that are very rich. You may consider that the carburetor is continuing to drip into the manifold after shutdown and causing the heavy carbon deposits on those two plugs. Depending on the manifold layout if that even makes sense, I have experienced a similar situation with my six pack.

Click to expand...

On the right track here ^^^^^.
Now let's take a look at the orientation of the 4 bbl on the 6 cyl intake manifold. the 2 main Run Barrels are on the front half and the secondaries are on the back half.

In a perfect world if rotated 90 degrees to the right then the 2 main Run Barrels are lined up even to flow to all 6 cylinders, same with the secondaries. Check your float levels so it is not dripping in fuel after you shut it down.

Get us a picture of how your carb is sitting there on your engine, maybe we can spot something.