283 wont idle
Is the vacuum line for the PVC valve plugged into the carburetor? Is the vacuum line from the brake booster plugged into the back of the carburetor? Get a can of carburetor cleaner and spray along the intake where it bolts to the heads. Also spray in front and back of the intake along the china walls. Check the carburetor base gasket too. If the idle speeds up more you have leaking intake gaskets. Set the timing to 12* BTDC starting out.