i think he would need a thermoquad
not sure if it'll fit, but i think it should

 

yes it will fit but the ports on the intake might be smaller than the 340 head ports. [if that is really a 318 intake. I didn't think that a 318 4bbl was made in 1980]
Any spreadbore carb would work. I like the q-jet.
[Another option would be an adapter to go from the spread to the square bore pattern to mount a holley.]
If in doubt, measure the openings of the intake ports and compare them to the port openings on the heads. If the difference is not that bad, you could port match the intake to the head. {using a 340 gasket as a pattern}
If there is a big difference,then dont bother to use that intake on the 340. Find a 340/360 intake. [summit has a good version of an air gap type manifold that is priced affordably]

 

I just looked up that intake number and yes it will work on the 340 with no problem.
I guess Chrysler did make a 318 4bbl in 1980 and apparently they must have used 360 heads on it because the same intake manifold is listed for use on the 360 engine.
The 360 has the same size ports as the 340 basically. You should have no problems except finding a carb! Enjoy.........