----Had a shadow grey 70 RS Z with horseshoe back around 1979 or so. You are right, Mark, they are a blast to drive. Leave the shifter in low and let it shift itself for a really fun pass! Funny thing was I found out a couple of weeks into my ownership that the car was originally yellow. Never bothered to check the trim tag and the repaint was well done. Took the car in trade for a 435 67 Vette and sold it after I discovered the color change..…Bill S

I love the horseshoe automatic Z28's. I wish they had a similar look in the Corvette.
Mine was a 1970 with 4:10 gears. The "BAM" into second was a blast.

What was the rationale behind having a 1 piece grill and a 2 piece grill?

It seems to me the RS would be better served with a 1 piece grill since it is more "exposed".

Just guessing but the limitation of injection molding it as one piece may have limited it. Actually, the one piece grill isn't truly one piece. There is a chrome edge that snaps on to the egg-crate grill that together make the complete grill.

The RS grill has a center bar that was also an integral part of the impact design which may have necessitated the 2-piece grill.

Did anyone check the deck stamp photo?
I don't know as much about 2nd gens however something looks odd to me...

My 06C Norwood 70 Z/28 has just the assembly date on the pad and the VIN by the oil filter. Is it true that California cars only had the VIN on the pad?

This is the norm. There are perhaps exceptions out there, but they are seem to be pretty rare in my research.