need some help with my dash cluster

[CIRCLEWORK]

hey all i own a 97 vt comm 3.8L i have recently put in a vt ss dash cluster 5.7L into my car now the problem im having is my fuel gauge goes spastic i fill the car up to full all is good but when the fuel gauge get to a quarter of a tank im empty the lcd display says i have 80 ks till empty but its full of s**t because i ran out of fuel one day in the pouring rain its was not cool. but any help would be really appreciated

[Sabbath']

Have you had the fuel calibration setup on the new cluster?