I looked at a photo of a LA built car's POP and noticed that it didn't have any data except the buyers name/address and the VIN. The car was sold in Colorado. Was this normal practice for some dealers?

No, the POP was done at the factory, but yours may be a replacement POP. I have seen a couple and they are like you are describing.

Sounds like a warranty extension plate.

Protect-o-plate on my 68 has buyers name address along with codes for radio, gear ratio in rear and other features. Unfortunately my car is a base L6 car with not many features

Thanks guys. That is also what I thought - a replacement or warranty transfer POP.