Scored Main Cap Bearing - Ouch

In post #13, the rear-most portion of the crank looks discolored (as in turning purple from heat), if those bolts rubbing on the back of the block caused that amount of strain, the front face of the thrust bearing (#3) will also be chewed to ****, there's your engine contaminant. The heat from those rubbing bolts would also have melted the rear seal! Take #3 cap off and see what damage is done to the thrust surface of the crank.