Probably "historically relevant" is not to the point, especially since it seems MChristensen is not expressing himself very well, and by now, knows it. If I were doing this, I'd want to look at bikes of vintage construction, of good quality, and in good condition - many Italians, better Schwinns, nearly any UJB, classic steel in good condition. Good condition so that there are minimal problems while dismantling and re-mantling, and so the the parts look as they really do - not having to deal with any significant distorted features. Good quality because better bikes and parts are less likely to be damaged, they are easier to build. Vintage or vintage-style because the config's of these bikes are excellent representations of many bikes, and need only small variations to be expanded to modern bikes. Plus, minimal carbon to deal with, so less likely to be damaged, again.

Freebie bikes are likely to be rustbuckets, a major pain to deal with as we all know. Plus I'd want to be studying complete bikes, not partials or boxes of parts.

I can totally sympathize with concern about theft, unqualified monkeying with a prized collectible or just something I put hundreds of hours into. I would only send my Masi or Mondonico to someone I know is capable, careful, and trustworthy.