I tried doing a search, but didnt see the exact info I was looking for. Sorry if this topic has been beat to shi*t. Anyways, I am ordering some stuff today for my spring time tune up and would like to replace the coil along with the distributor cap, rotor, wires and plugs. I think the coil that is on there is still ok, but at the end of the summer I started to suspect a spark issue, but I am no expert so I'm not sure. That being said, for $50 I can get a new coil and then I would not have to worry about it. The motor is a mostly stock 502 mpi and am wondering if I should go with a new OE Mercruiser coil or an MSD Blaster or Thunderbolt? The rest of the ignition is stock with the exception of what will be 8.5MM MSD wires and AC Delco plugs.

Ive had good luck with MSD high vibration coils.

Thats what I was lookign at. Are those pretty much a "Plug and Play" install when I do the wires and cap?

Check Davis unified ignitions. Their stuff is plug and play also. I have never had any problems with their stuff. They have great ignition wires. Also great customer service. I measured my ignition wire set, for custom made set they were at my door in a week.