Check the alternator if that don't do it change the battery
Check the timing.
Wrong starter, wrong fly-wheel, Bad starter drive, worn fly-wheel. Starter may need to be shimed.
If I can remember it correctly, there were 4418 81 Chevy Caprice 2 door Landeau Edition...if I'm wrong please correct me here...
Loose, defective, or corroded cables, loose ground wire, starter, or starter solenoid.
You may need to check the flex-plate where the starter makes contact to the ring. If it's damaged or worn you'll need to replace the flex plate.
is it possible that the vent hose are disconected?
distributor cap
It could be a bad starter, or a weak battery. The clicking sounds like the solenoid is engaging, or trying to engage.
Two MOST probable in the order I'd be checking....Low battery charge or defective battery....Loose or corroded battery cable connections. Secondly, you possibly have a defective starter or starter solenoid. Good Luck! Dub
possiblly the starter or fuel pump is out.
You need to remove starter again and look at the ring gear. Turn engine by hand and inspect the ring gear teeth. Be sure they are not damaged if okay you probley have the wrong starter. some times you have to shim the starter. NEUTZ
Don't hold me to the fire if I'm wrong, but I'm almost certain that it has 260 horses