Indeed I have in fact searched it on google. Oldmercs.com it’s unavailable. As well as marinengine, mastertech, Crowley and every store I can find including Mercury. eBay has parts manuals but no mercury marine service manuals for my engine. Ive been through other forum discussions with other links and no luck. Mostly old dead links. I do have the original Clymer manual but there’s no mention of ohm specs and it covers a wide range of motors.
I think the V6 of that era had different ignition coils than the other blackmaxs. I could be wrong. I’ll maybe send some emails to the above mentioned and see if anyone can help locate one.