I bought a pair of these feed through terminal blocks since I have my battery in the back, and didn't want to use O rings to insulate the power cable from the body.
After looking at them, I noticed that if installed incorrectly, the terminal could short out against the the body where the hole was drilled. And naturally they didn't come with any instructions as to which way they were to be mounted. The correct way to install them would be to drill the hole large enough so the red insulating collar would protrude through the hole in the sheet metal. Then two more holes for bolts and nuts to secure the terminal to the sheet metal. I decided not to use them, and I'm using a Moroso through terminal. Only drill one hole and the terminal is held in place by a large nut, and it is fully insulated
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