Thinking back... I think that when I mounted my Mark-rebuilt and tuned carb, I had the same sort of high idle issue. I had forgotten this, but I definitely had a problem getting the idle down.
Until I thought of the fast idle screw... turned out that Mark set the fast idle screw up (fast)... for some reason.
He had a legit explanation, when I asked him about it, but I can’t recall, now, what it was.
Try adjusting the fast idle screw to allow the basic idle to idle slower.
Check the picture Mark (@65swb45) labled, in post #6 here —> Tuning the carburetor in a 77 fj40
Edit: Actually post #7 has a labeled picture.
Until I thought of the fast idle screw... turned out that Mark set the fast idle screw up (fast)... for some reason.
He had a legit explanation, when I asked him about it, but I can’t recall, now, what it was.
Try adjusting the fast idle screw to allow the basic idle to idle slower.
Check the picture Mark (@65swb45) labled, in post #6 here —> Tuning the carburetor in a 77 fj40
Edit: Actually post #7 has a labeled picture.
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