A833 + clutch question : 68 318 engine

there is a difference between a pressure plate and a big chevy flexplate and a powerglide car does not have a flywheel. pressure plates-clutch cars-are balanced neutral at the manufacturer. when it is bolted to a flywheel there can be some slight error. so when we balance an assembly we suggest a pressure plate is with it and we spray paint a line on the pieces. most mere mortals do not rebalance when a clutch assembly is replaced-and do not need to. try to buy a replacement pressure plate made in USA