The surname used to vary depending on the region and alphabet, the main versions are Hulewicz/Gulevich/Goulevitch/Гулевич.
The major settlements were in Poland (Poznan, Lublin), Ukraine (Lviv, Lutsk), Lithuania (Siauliai, Vilnius-Svencionys), Belarus (Molodechno, Gomel), Russia (St.Petersbourg, Moscow, Smolensk, far East).
All information is appreciated and welcomed! DNA testing is encouraged too!