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-----2 ^ 4 the arrow is the rotor pointing at #1
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i had issues with this last summer too, as TDC wasn't where the book said it would be. just couldn't get her to fire, even tho i triple and quadruple checked everything. the firing order you mentioned before was correct for mine (altho mine's a 12V, and i don't know if that would make a difference), and sounds like your vacuum advance is in the right spot too (about 7 o'clock-ish). i'd give james' suggestion a try, in pulling off the valve covers to mark where your TDC is fer sure.
if it still comes up in the spot you've been trying, check that your plugs are in the right spots; then have someone with fresh eyes check 'em again. when i called in a friend, he spotted the switch plugs in two seconds, and next thing ya know, she was purring like a kitten.