Don't know if you've got one sittin' around, but for the sake of argument a stock 360 2bbl manifold and carb is an excellent bolt-on addition to a stockish 318. All your planned linkages will work. If you don't have one already, they can be had for a song. View attachment 1716453658
Adding this to a 318 does not work, 360 ports are to big. i know from experience, engine will not run right until full operating temp, i removed this and went to the original 318 intake then all good