Diagnosing no start on 1993 SN after winterizing

Background: relatively new boat to us. We had starter and carb replaced at the end of last season, then winterized.  Winterizing involved removing drain plugs/draining and putting in fuel stabilizer. Brought it out of storage a couple of weeks ago to prep it for summer.  Did a quick oil and filter change, along with putting in new spark plugs.  Then replaced the transmission oil cooler, since i accidentally broke it while getting ready to start the boat up (using garden hose as source of water). Took battery out and charged it with a trickle charger over night.  It is now back in the boat. 

Now I'm unable to start the boat. It turns over but won't start. On the advice of another post I found here, I removed the carb cover and checked whether there is fuel getting into barrels when manual actuating the accelerator flap. Not seeing any fuel spraying or smelling any fuel.  

Attaching a couple of pics for reference, in case I accidentally put this back together wrong after winterizing. What steps should I take next to diagnose?  Thank you for any help you can provide.