The Fuel, Temp and Oil are held in place by two V arms, one inverted, that work in a push-pull fashion as the bimetal strip bends. To remove the needle you need to remove the face, then CAREFULLY remove the pointer.
The Ammeter uses the same type of soft aluminum pointer, but is only removable by bending up the arm that the pointer pivots on.
DO NOT pull on any of these pointers! The pointer assembly is VERY fragile stamped aluminum and will bend out of shape if you look at it too hard. If you are going to disassemble the gauge, take pictures so you can see how to reassemble it.
The tachometer has a plastic pointer that is pressed onto the movements pivot shaft during assembly, then a spring piece is stamp welded above it. It is not easily removable, but is EXTREMELY fragile plastic. I do not recommend trying to remove this pointer unless you have the tools and equipment to re-install the pointer, balance and calibrate the tach.
The speedometer pointer does pull straight off. It is stamped aluminum, but not as fragile as the small gauges. Pull from the center hub, not on the pointer itself.
The pointers are not the same as earlier (pre '71) Mustangs. The four small gauges will interchange physically and functionally, but aesthetically they are shaped differently.
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