I so know that and I just keep on putting it off...

Facepalm.

I just realized I did not seal the head bolts that go into the water jacket. That's a much more likely explanation.

Bringing it to the house today to fix that and reseal the intake.

I feel like an idiot but I thought it might help someone else if I confess.

I'll update how it idles after things are redone.

Un-Facepalm. I found the head bolts actually were sealed. I only thought I had messed up. But I HAD botched the intake installation.
So after I put it back together carefully following the Mercruiser process I tried to start it and got no run with the abused NGK heat range 5 spark plugs
Then I put in some NGK BR6FS (OE) plugs which are heat range 6. The middle # on NGK is the heat range BTW. Gapped them to .035.
Engine lit right off. Once I set the timing and idle mix it idled for 10 minutes at 775 rpm on the hose. Next stop Lake Winnipesaukee in 2 days when I am off work!
Hopefully this is put to bed.