Not sure if it's good form to post this, because I haven't tried it, but: I found a freeware/shareware 6502 Visual Simulator which offers an [http://w3.gazi.edu.tr/~nurettin/visual_tr.html]animated block diagram[/url] mode.

Here's the diagram it animates:

(It's not identical to a real 6502 - it has 3 incrementer/decrementers and looks like it might follow a strict fetch/decode/execute sequence. At least it lacks a B bit, as it should!)

(It's by a Dr Topaloğlu who teaches Computer Organisation and Computer System Design)