Though yesterday was pretty nice up in here the great north, I have not had this boat on the water and do not plan on it before it gets put away for the winter.

have you disconnected the throttle cable to see if its binding

I have not. The throttle is pretty stiff though and can be tough to get into nuetral/reverse.

Is there supposed the be idle mixture screws in both the front and back of the carburetor? I have 1 on each side in the front and none in the back.
https://cimg3.ibsrv.net/gimg/www.off...7d9ae72ea0.jpg
https://cimg7.ibsrv.net/gimg/www.off...ec8a2a8a4e.jpg

Idle is only on the front 2 barrels

BTW, those other larger screws are for float level measurement

Tried again tonight with another choke adjustment and to check for vacuum leaks. 3 pumps of the throttle and a little gas and it fired up and was actually idling around 1000 rpms. Tried to quick check timing but couldn't see the mark on the balancer..
So the I checked for vacuum leaks and nothing obvious popped out at me. But the warmer it got the more it would stall, and by the time I was done checking for vacuum leaks it was closer to 2000 rpms it had to run at without stalling

How did you check for a vacuum leak?

Remove the flame arrestor and with it running, look down the carb to see if fuel is dripping down the throat of the carb

So it doesn’t run at 1500rpm on its own, you have to hold it there to keep it from stalling?
Picture of carb looks like mixture screw is way out to me. Turn them in all the way(gently) then back out 1 and 1/4 turn. It should run there and adjust later.
I would remove flame arrest or, run engine to warm up, and when you bring the throttle slowly down to idle when it starts to die out give it a short burst of carb cleaner in the top of the carb. If you can keep it running that way you know you have a lean problem. Be careful, carb cleaner is flammable.
Did you check around carb base plate for vac leak? Does it have a PCV system? That’s another possibility for vac leak.

WD40 around the carb base gasket and all around the intake.
There is fuel going down the throat of the carb when it was running at 1500 rpms, it dies immediately when I back off the throttle so I cant get back there quick enough to see what's happening at lower rpm.