versions/percent? http://forum.wbfree.net/forums/showthread.php?t=22022&page=1 thread tended to be russian, but pictures are self-explanatory.
from 109e-3 to 109g-6 -before e-3 no headrest at all. -from 109E-3 to 109G-2 armored headrest -and from g-6 onwards plexiglass armor. Bf 109g-6 (erla canopy and plexi glass armor) BF 109g-6 (normal canopy and plexiglass armor) here's a finnish site with complete listings of canopy/armor types: http://www.jiop.fi/ksimuseo/faq_bf109evocanop.html
Illo, what are those red lines on side cockpit windows? Are they visial horizon controls for dive bombing or what?