If any of those marks are visible in the timing window and everything else is aligned properly, the engine will start. It might not run perfectly or get the world's best gas mileage, but it will run. It's just not as critical to get everything letter-perfect as some people think. Having the distributor engaged with the right tooth on the camshaft, and properly engaged in the oil pump, plus making sure the spark plug wires are correct is vitally important. A few, or even several degrees off of perfect at the flywheel marks is about #12 of the 10 most important details to be concerned with.
Jerry
