Most S100 cards used only standard chips, and the
manuals were normally
excellent giving full schematics (and programming data for PROMs/PALs if
any were used).
Speaking of Cromemco cards, and only using "standard chips", does anyone
have a source for the TMS3417, used on the Cromemco Dazzler? Google only
turns up a single mention of it, on a German page. "Standard chips"
aren't necessarily all that easy to find. (But much easier to find than
gate arrays and other ASICs.)