find a donor... do you have a good salvage yard nearby? pull parts of one--may be tough finding a manual - equipped old chevy. Buy an old wrecked one and strip the parts off.
But, you will need the whole nine yards....driveshaft, bellhousing, clutch pressure plate, disc, throwout bearing, linkage, clutch rod, fork, trans crossbar, mount for clutch linkage/rod, pedal assembly, and most likely will have to fabricate the hump. Lotsawork.