Looks like you got the model of the carb figured out. I found that there is a stamped number in the housing front face. It is to the Left and below the fuel input line when looking from the front. Mine was stamped R40198-1 which meant more to the parts guys than telling them it was a Holly 2280.

Looks the the vacuum line just below the fuel connection on the front is cut off and has a bolt in it!? This is supposed to go over to the vapor canister by the Right wheelwell.

W150 1984 318.

 

Lol yeah that is off. Both of the lines going to the vapor can are sealed off. Thats from the guy before me, he says the vapor can is not good. W/e its running. lol