There are several places to find cowl hoods,,,,LMC truck,,,harwood,goodhoods,and probably the cheapest ebay....
check with yearone.com. I've got a 78 Nova and this is the only site I've ever found to have the cowl for this year http://www.up22.com/nova75.htm
cowl induction
buy the emblems, peel the backing off the emblems and stick on the side of the raised part on each side of the cowl induction hood.
cowl tag
This is the COWL , high pressure area for heating and air cond to obtain air from the outside. Old school "Cowl Induction" to get fresh cool air for the carb. Bill
separate a timing connector on the firewall in engine bay which allows you to time the engine,then adjust the distributor.The connector is on the drivers side below the cowl and when separated the engine will run differently.
This works, by having a reversed intake, and the faster you go, the air goes down the windsheild, through the hood, and into the intake.
You will need the bumper,grille,head lights,rad support,fenders,hood, cowl. This can be done with some mods. 73-80 had different front frame horns for the bumper mounting. They were closed off and square. As for the 81-87 (88-89RV) they were open and cut on a 45 degree angle. Your windshield cowl on the 1973-80 were built on the hood. Where as the 81-87 (88-89RV) had a separate cowl that bolted on to the cab. Hood hinges are going to be needed as well.
That would be the panel between the bottom of the windshield and the rear of the engine compartment hood.
check your vents on back of cab
Underneath the winshield cowl, drivers side
Its attached to the windshield wiper motor you will have to remove the cowl to get access to it.