Would like to get a copy of a 1964 Chevelle buildsheet for my own use to get some of the codes for the options and what tags would have been on the shocks spring and such Thanks guys

Heres a RPO list. http://www.chevellestuff.com/1964/options.htm
As far as I know, 64 did not have "build sheets"

A build sheet in a 64 is very rare, they were probably tossed in the trash. There never was any mandate to put them in the cars, some got put in the cars by the workers cause there was no better place for them.

I never found one in my car or the parts car that I used to restore my car the first time in the 80s.