Volvo 5.7 gi-e spark plugs & voltage regulator

[Shark_bait99]

Hello all,
The ice is melting and it's almost time for boating season. Hooray!!!

And time for some more boat repairs...

I found one of my ignition cables in the bilge at the end of last season, so I figured it was a good time to replace the ignition cables and spark plugs on my 2004 four Winns w a volvo 5.7 gi-e w sx-m drive.

I just wanted to confirm the iridium version of the ac delco 41-993 plugs are correct and better than the volvo/champion plugs (21467472).

I have also been trying to figure out a low purple wire voltage to the ignition and the "excite/sense test" (positive multimeter lead to L stud, negative to battery ground w key in on position but not started) gave me only 75 mV where the service manual says anything other than 1-2 V indicates the voltage regulator needs to be replaced. See my previous thread for more details if you like...

I have found an oem regulator on ebay

My question is, are these both fairly straightforward replacements?

Specifically my concerns are, is it common to break the spark plugs that have been carbonizing for 10 years? I was thinking of using a torque wrench to remove them and staying below 30. I have 5/8 spark plug sockets w the insert and the appropriate extensions if needed. I have read that you could loosen 1/8 turn then spray the plugs w carb cleaner and soak overnight to soften carbon and make removal safer if they are sticky.

Second, can I replace the voltage regulator without removing the alternator? My plan is to disconnect the battery, label and remove the alternator leads, unscrew/unbolt the back cover, replace the regulator, screw everything back in, and finally coat w liquid electrical tape.

Thanks in advance for all your input! Happy boating!