Tyler, a few observations.
Electric oven owners have the luxury of working with larger vertical gaps because electric broilers are more powerful than gas. To achieve the top coloring that you're looking for, put the plate on the top shelf. Working with a small vertical space might take some getting used to, but, launching smaller pies is easier in general, so it shouldn't be that difficult. As you graduate up to a real NY style pizza size and comparable size plate, that's when the miniscule vertical gap might start being an issue.
It takes 25 minutes for the oven to pre-heat, but the plate is thick, so it takes longer for the heat to penetrate. You might be able to fully pre-heat the plate in 45 minutes, but I'd give it 75 minutes, just to be sure. If, once you have the pizza you're looking for with 75 minutes, you can then start to dial that pre-heat time down and see if it makes a difference.
Pre-heat the plate to 525. If you pre-heat the plate to 525 for the full 75 minutes, it should have no problem with a good, slightly charred 4 minute bake and the lower temp should prevent the thermostat from shutting off the broiler. Watch the broiler and make sure it stays on for the entire bake. If the broiler does cut out, then you'll need to try something else. There's gentle oven tricks that will give you a slight 25 degree boost and allow the broiler to stay on, but I won't go into those until I'm sure you need them.
Use a wood peel for launching and a metal one for retrieving. You never want to get raw flour from the launching peel on a baked pizza, because the flour has a bitter taste. Also, wood is a lot easier to launch with, because the skin slides off of it easier than with metal.
I hand mix and knead everything, about 10 minutes. Bulk rise for 6 hours in a covered bowl on my counter.
Are you sure this is a 'bulk rise?' A bulk rise signifies multiple dough balls (in this case 3) fermented as one mass and then divided. If this was in bulk, how long did you let the dough balls proof after you formed them? If you are using a bulk a rise, than I suggest, for now, simplifying the process and fermenting the dough balls individually.
I can't quite put my finger on it, but something seems a little off about your dough. I'm not in love with KABF, but quite a few members are able to overcome KABF's shortcomings, so I don't think that's it. You are using a digital scale to weigh the flour and the water, right? Are you using a scale to portion the dough balls as well? The reason I ask about the scale is that the thickness factor seems off. The formulation is for 8", and, from the photo, it looks like an 8" pizza, but the crust is way too thick. Are you having trouble stretching it to 8"?
One of the biggest barriers for beginning NY style pizzamakers is being able to stretch the dough thin enough. 'Overbaking' is not the issue here. If you take a chewy thin crust and make it a bit thicker, it will start getting tough. Two things. Watch this video a few times (ignore the rolling pin part)
and make an extra dough ball or two and stretch them as thin as possibly can. You won't be able to use the skin once you're done with it, but this is a really good and relatively inexpensive way to master stretching.
Lastly, I'm in not in love with this recipe. If you are only fermenting the dough for 6 hours, that's really not enough for NY style. NY style, ideally, should be cold fermented at least overnight, and you'll want to use enough yeast for the dough to double in the time frame. .2% yeast seems a bit low. As the recipe stands now, are the dough balls doubled in volume by the time you bake them?