I am rebuilding the Quadrajet on my sons 84 GMC. I did the one I had on my '72 in the late 90s so it's been a few days since I've delved too deep into one. My concern is there is no plug covering the Adjustable Part Throttle screw. My other one had an aluminum plug covering it. I was googling images and I've seen pictures of carbs WITH the plug and WITHOUT! Is the plug necessary?
Plug and hole are circled in red