Was dinner time, sorry.
The V-8 engines common to us all turn the distributor 1/2 speed of crank, so whatever plug wire is opposite #1, fires at TDC .
In all the engines I can remember it was #6 . There certainly may be exception.
Same with 6 cyls and 4 cyls .
Our scopes were between bays, so was convenient to swing the boom and use the plug wire either side .
Cheers
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