Caveat: Not a teacher — just a simple DP who had to learn this stuff the hard way
Yep. "Year" is the object of the sentence alright. It just happens to be modified by the adjective "great", but that doesn't change its status as the object of the sentence.
Here is the full Monty: "It" = subject; "has been" = verb (or predicate if you want to get highfalutin' about it ; "a great year" = object.
So what about "for Bill and me"? Well, actually, because the only function of those words is to modify and explain something about the object, they are part of the object, really, so that the words "a great year for Bill and me" may justifiably be considered the object. "Augmented objects" (my term) are common and are properly called object clauses, just as when you modify a simple predicate, it becomes a "predicate clause".
Anyhow, glad to hear the good news
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