Thanks for the good advice.

I run this engine at idle for long periods of time (trolling), and have always use a good / high octane gas. I have never had problems with plugs fouling or adjustments before, the only thing I can figure is that I ended up added more oil than needed the last time I filled the tank.

The big thing here for me was the oil type and having the mechanic say that you should only run specific type oil in your gas it seemed to be a reach.
From all the research I did the TCW-3 oils are pretty consistant across the board, so I am going with a Pennzoil oil that formulated for older motors, it meets or exceeds all the specs on TCW-3 oils, and cost less than the Evinrude oil.

Guess we will see - may have to paddle some if I'm wrong.