I 'd add that testing the coil – (negative) terminal with a +12V test light can also be helpful,

With the key on, a test light at the negative terminal should be bright (+12V "reading" thru from the + terminal).

If no light, either the coii is bad, OR there is no voltage at the + terminal. (further testing needed)

If the light is bright, it should go dim and pulsing when the engine is cranked. Failure to change from "bright" means the Ignition Control Unit (ICU) is not triggering the coil. (further testing needed)

NOTE: Looking at the Haynes diagrams (reluctantly), it seems that the '85 740 Ignition doesn't have a "Power Stage" as suggested above. The ICU triggers the coil directly, based on timing pulses from the distributor.
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Bruce Young
'93 940-NA (current), 240s (one V8), 140s, 122s, since '63.