G'day Caps if you put the YZ bits on the DT1 it won't be pre70 it will be pre75 its up to you the way you go.I've got a DT1 and its got bits from all over the years on it.I made my seat from a XT seat base I just cut the base to make it fit and then fiberglassed over the cuts now I have a seat base that is lighter and won't rust.