https://www.ebay.com/itm/1968-NOS-ne...p2047675.l2557

Wow, if this is the frame, it might be suggested that it not be built up but rather left in it's pristine condition. If it must be built up, it would be neat to source all the parts as NOS as well. Hanging any crusty used parts on that would be ugly.

This frame was probably a custom order, so adhering to any standard parts spec would not necessarily be important...it should be built as someone imagining their dream component set back in 1968.