The problem is, there is no way to tell if that build sheet is the one for your car. The VIN is missing off the sheet. I've found many build sheets from other cars inside any given car. The only codes I see on your fragment is 623 (heavy duty suspension) and 358 which in '68 should be a performance axle/heavy duty cooling package for a 383 car which your car is not. Get a magnifying glass and look closely. If you see any other codes, point them out and we'll do our best. The fender tag codes will help more.