I'd guess that a rebuilder's tag would be an uncommon collectors' item.
I have seem many rebuilt 216/235/261 engines and never saw a "tag".
However, my first junkyard engine (a 261 from Leon's parts yard in 1972) was out of a well-maintained county school bus. The last rebuilt specs (.060 pistons/rings) was stamped into the block.
If anyone has a stovebolt rebuilder's tag (or, rebuild markings), would you please post a photo?
