Need advice about 1972 Evinrude 50 hp...

I bought a 15ft kingfisher 6 years ago with a 1972 evinrude 50 hp electric shift. It ran rough when I bought it, the first few years, had the carbs rebuilt along with a new waterpump about 4 years ago. It ran awesome for about 6 months and I left it up and didn't put stabil in the gas. It sat up for around 4 months or so. I took it to the river and it was running fine for about 5 min and then it slowly died and hasn't cranked since.

I took the carbs and fuel pump off and was gonna clean/rebuild the carbs and replace the screen/gasket on the fuel pump and never got around to it.

All the gears worked fine for the first few months, then when in reverse, it would barely pull the boat back. It finally got to where reverse most of the time wouldn't work, every now and then it would. I drained the fluid and filled it with Evinrude/Johnson premium blend (for electric shifts) I think twice since I bought it. I think it had a little bit of water in it, can't remember the exact color, it's been awhile.

I had 3 shops do tune-ups, one every year. The first two sucked and the last guy knew what he was doing and that's when it ran great.

My questions are:
What would you do?
Rebuild the carbs/fuel pump, if it works, keep running it?
Take the lower unit off and inspect/replace parts?

I really don't want to put a bunch of money in it, but I really would like to get it running for at least another year or so, until I can get money for a newer motor. Thanks!

Re: Need advice about 1972 Evinrude 50 hp...

You said it slowly died and wont crank. Are you saying the engine wont rotate. Is it possable the motors sized up? as far as the issue with the lower unit. Did you fill it from the bottom of the unit to the top plug or did you just pour it down the top?
You really dont need to rebuild your carbs EVERY year if you treat your fuel right.