Anyway here's the working progress...
1st stage (very) quick roughs:
Chosen rough development - I drew the parts seperately then scanned them and composited in photoshop - added a bit of tone and jigged the text around:
Work in progress 1 - drawn up in illustrator:
Work in progress 2:
And the final piece - drawn up in illustrator but then taken into photoshop where I added the textural qualities and altered the tone in the background areas: