WICHITA - A restaurant received extensive fire damage early today in west Wichita. Just before three A.M. firefighters were called to a Taco Bueno in the 300 block of south West Street. Wichita Police officers in the area saw smoke coming from the building and alerted dispatchers.  Wichita Fire crews arriving on the scene found smoke and flames in the kitchen area.  The fire was reported to be under control after 30 minutes, but severe damage had been done.  Fire officials have given a damage estimate at $100,000 to the structure and another $100,000 to the contents in the building.  The cause of the fire is under investigation.