Is there any way to "verify" that the offsets I have used are in fact the correct ones? Since this is '93 batch fire injection maybe I won't be able to tell that much?
for a car like yours if it runs good enough now, your offsets are probably good enough to continue tuning. just go with it.

I do still see the injector driver errors popping up, and the ERROR still shows on injector banks 1 and 2. I'm not sure I feel any effects from that.
are you sure about that error code? what scan tool gives you the error? what are the error numbers