I have a habit that whenever I buy a car (or component) which has original tags, I copy them down in my notebook along with casting dates. This really paid off recently when I brought "Mindy" home (built in early May 1965 with a March, 30th 1965 cylinder head casting date) without an engine tag. Luckily I was able to go back in my notebook and find the tag data for the replacement engine which was installed in "Cassie", which was identical except for being made in February. I just changed the date code from 5-B (1965-February) to 5-D (1965-April) and had MartiAutoWorks make a replacement tag using all the other data from "Cassie".