Yes...interesting topic. It's easy to pinpoint my very first memory...and it involves a car too. I was watching my dad affix the yearly registration tag to the front license plate of his green '52 Chevy...the tag read "53" which made me 3 or 4 years old at the time (depending on what month the registration was due). Back then in NJ, the tags were stamped metal (probably aluminum) and were attached by sticking two tabs thru slots in the plate and then bending them over.