Happy Chinese New "Dragon" year to all

i bought a tacho meter 5" from a friend,send it to a workshop to install it.da prob is,da tacho is for 4 cylinder but my car is 3.i dont mind bout it coz ill be changing to 4cylider soon.annddd...my shift light dosent blinks.only the small green on the tacho blink but not the small long round red light on the side of the tacho.is it becoz of the difrent cylinder or something had gone wrong with the light?its already being installed and all wirering are okay. coz my friend said even da...