Guys,
I tapped into the Wikipedia for info about this WWII aircraft and found this very interesting:

From the inception of the design priority was given to total and easy access to the powerplant, fuselage weapons and other systems while the aircraft was operational from forward airfields. To this end, the entire engine cowling was made up of large, easily removable panels which were secured by large toggle latches. A large panel under the wing centre section could be removed to gain access to the L-shaped main fuel tank, which was sited partly under the cockpit floor and partly behind the rear cockpit bulkhead. Other, smaller panels gave easy access to the cooling systems and electrical equipment. The engine was held in two large, forged, magnesium alloy Y-shaped legs which were cantilevered from the main firewall/bulkhead. Each of the legs was secured by two quick-release screw fittings on the main firewall. All of the main pipe connections were colour-coded and grouped in one place, where possible, and the electrical equipment plugged into junction boxes mounted on the firewall. The entire powerplant could be removed or replaced as a unit in a matter of minutes.[19]

Not to pick on Chris, but if our experimentals were so designed it wouldn't be so hard to swap engines or rebuild them.  Cars too.
Just food for thought.  BTW, there was more about quick service to wings and other systems.

http://en.wikipedia.org/wiki/Messerschmitt_Bf_109


Jim Brewer