If I had a choice I care more about an original sheetmetal car. Whether it a Z/28, COPO Yenko etc. I believe the first buyer started out buying the car he saw on the show room floor. The main attraction was the Z/28 or SS package (style trim) then I think the performance parts played into it. If you bought a Yenko in 1969 and warranty replaced the motor in 1970, would that bother you more than if a body shop put your drive train in a 1969 donor car in 1970 after you totaled the car? The donor car really isn't the car you bought in my opinion.
