These numbers are very loose I suspect. The coil is basically a high voltage transformer, many of which i have designed. Since you are measuring basically the resistance of a length of wire, it is not exact. And as you say, your meter may be off.
In these tests you are really looking for shorts or an open, of which you have neither.
But, i should point out that the test is far from conclusive, the coil could arc internally, most likely in the secondary, and this test would not show that.
Two things to check which i have experienced on this vintage car.
The wire to the ignition control box passes over the alternator. This is a shielded wire. Mine wore against the alternator housing producing intermittent shorts.
Check the wiring and condition of the ballast resistor, located on the firewall under the wiper motor.
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744-16v,745-16v,242Turbo.245DLT