It looks to me like you have altered the angle by removing material from the bottom of the heel cheeks. Now the dovetail is no longer tight, particularly at the bottom. Generally you have to shim the bottom of the sides of the joint more than the top, I glue the shims in then taper them with chisels and sanding blocks. It helps a lot to chalk fit them - you can see where you need to take away material.

I also think you have confused things a bit when you sawed the f/b off - frankly I would have left that off until the neck was set, then tried to glue it back in place over the joint and onto the body.

Are you using the sandpaper strip technique to fit the cheeks of the heel to the side? If you're lifting up on the strip when you pull them then you could be sanding the heel at an angle. I can't see what you're doing so it's hard to tell.

Is this a particularly valuable guitar?

So I've discovered that the bottom of the dovetail joint is pushing up against the back of the pocket which is forcing my heel out and not letting it close. None of the things I've seen on neck resets, (John Hall, Dan Erlewine, Frets.com, etc.) mention this in their processes. It seems simple enough to take a little material off the back of the joint to allow space for the joint to pull back in. But I don't want to do that if there are unforeseen consequences. I don't know if the amount of space behind this joint is normal or not, but there sure isn't much room.

I've removed a slight bit of wood on that portion of the heel on each reset I've done, moreso if the neck was severely out of whack. I can say from experience that the ones where there is no gap (filled with glue or just fit too tight) are the most nightmarish ones to work on, because when you remove a neck you need steam/heat to reach those portions of the neck, if it can't reach it then you have more problems.

Remember the sides of the tail are where you need the most glue surface. If you're changing the angle of the neck enough then it makes sense that the neck would fit in the socket like this.

Just remove enough that it leaves a slight gap at the bottom so that should the guitar even need another reset you don't drive the next guy up the wall with a dovetail that won't budge. I remember talking to a guy who specialized in cellos with my lifetime worth of experience. His advice on gluing things together was "Never make it undoable"

Remember that when shimming the dovetail joint, it's far more important to have the heel fitting tightly at the bottom than at the top near the fingerboard. That's probably the reason that most of the literature omits the need to remove material from the end of dovetail there. We concentrate on having the tapered dovetail pulling in tightly so that the heel fits tightly. Some of us take it as self-evident that if the heel is to pull in appropriately against the body, there would necessarily need to be at least a small gap at the end of the dovetail down in there.