Regarding fitting speed governor....?

i would like to know the feasibility of fitting speed governor device in small cars such as maruti800 and alto. as per the government order in tamilnadu, most school buses have the device fitted by 'pricol'. we live in southern district of tamilnadu(corporation city). i learn that only coimbatore city in TN has dealers fitting the device. how about the cost ? can it be programmed(microcontroller based) to a max. speed of 45 or 5o kmph ?