Very thought provoking.With the valuations being what they are,and the less $respect NOM cars recieve,I'm sure the folks who are lucky enough to obtain original driveline cars are sure glad the previous owners took the preservation road.There are certainly enough CE blocks out there to validate the greater number that took the side stepping of the clutch approach early on in the cars life..just like when you went to super shop for $39.95 Hedman headers,and threw the smog and manifolds in the can,the significance was not apparent at the time.I have a 69 los Z with nary a stitch of paper-but the orignal DZ engine.If I decided to"enjoy" it and DX'ed the block,that would seriously affect it's value.It's being restored,and when done that engine will be on a stand and a 355 with Keisler T56 kit will be going in.Now if I want to rape it,no little man on my shoulder