I'd get that fire up sorted first - do you think its too much or too little fuel in the priming/cranking/afterstart area?
Adding easy start will give you some combustible gas to kick off the burn so it may be that you are too lean, conversely it might be that you're too rich because you've added 25% more fuel by having that other injector connected.
What I'd do is: crank the engine with your foot down on the throttle - this causes the fuel cut to activate, modulate the throttle on and off to inject a little fuel and see if the engine catches, if it catches with just a little bit of throttle modulation you're massively over rich so reduce the cranking pulsewidth by a few ms and try again. If it catches with your foot off the throttle more than its on, then you're nearly there so pull 0.5ms at a time.
Inspect your plugs throughout the cycle they tell you more about the mix at this stage than the wideband will.
As for feeling like a fool - DONT! this whole engine management system stuff is difficult, when I used to do carbs and distributor based tuning there were only a handful of people that actually understood what "Jetting" was (I was not one of them), yet hundreds claimed to have Jetted their carbs themselves
Nowadays theres a lot of "Mappers" out there and probably an equal number of them who actually understand what's happening. You've started the journey of becoming one of the latter
