we have 3 camrys of the same model at my place, and mines the only one with a tacho, im jus saying this cause other than look good it doesnt do much for me cause you can definatly feel when a 3s-fe is giving up (above 5,000) which for a manual is around the 80k mark in second
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on a side note i did think of getting a similar kit from jaycar and use the 16 hole vent above the central vents in the dash, but money and wasting another day seemed to put me off it.
and taking apart a camry dash is simple, all you need is a phillips head screwdriver (i dont know if this applies to all camrys (camries?))