This website contains about 400 photos detailing the various components and features of the 737. Here are links to some of those pages:
The Walkaround - A photographic tour of items not to miss on an external check.
Wheel-well - Wheel-well map, interactive quiz and all major components photographed and identified.
The E & E bay - Uncovered ! - Discover what lies behind this tiny hatch.
Landing Gear - Including what to look for in the downlock viewer.
The Flightdeck - Panel photos & descriptions of each generation of 737.
737-500 Flightdeck - A detailed photographic study of a 737-500 flightdeck.
Throttle quadrant redesign - New layout on NGs and MAX from l/n 5605 onwards
*** Updated 17 Mar 2016 ***