For the following scenario, identify the most efficient geographic arrangement, and explain the reasons for your choices. Identification of this arrangement should include as many of the following elements as appropriate: major and minor geographic units, encyclopedic or dictionary arrangement, lettered guide plan or location name guide plan.

A large aerospace company keeps its facility and equipment maintenance records by building code. The buildings and equipment include:

1. Assembly Plant: Belt 1, Belt 2, Motor 456, Motor 123, Lathe 3
2. Research Center: Computer 72, Mega Server 6, Small printer, Large printer
3. Fire Station: Hose 3, Hose 5, Extinguisher 23, Ladder 9
4. North Testing Laboratory: Oven 17, Microscope 43, Centrifuge 12
5. South Testing Laboratory: Oven 18, Microscope 21, Centrifuge 5