I'm currently working on this, and feeling very cross-eyed with it. Been a while since I worked on something detailed, and am really enjoying it.
I like to put a picture such as this into photoshop towards the end of its' drawing to test out details, so this has been digitally 'beefed up'. Will then go back and redo the 'beefing up' manually since I've now worked out where it's lacking. Don't think I can face it today though. Am at that point where I might grow impatient, go mental with my pencil and cock it all up. Might take a little walk and work on something else.
Am jolly chuffed I got to use the phrase's 'beefing up' and 'cock it up' in one blog post though. Tremendously satisfying. There's not enough 'beefing up' in my life!