4 cylinder 1-3-4-2 ===6 cylinder 1-6-5-4-3-2

For the 4.3L (6Cyl)
Firing Order:
1-6-5-4-3-2

Cylinders:
(back of engine)
| 6 |---------| 5 |
| 4 |---------| 3 |
| 2 |---------| 1 |
(front of engine)

Distributor:
...(back)
(+)..4...3
.5...........2
....6...1..(+)-screw
...(front)

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