318 2bbl intake on a 360

302s have the small 273/318 port size. Your '65 manifold will not fit any '66 and up heads, the intake bolts are a different size and angle into the heads.
Get a '66 and later 273/318 2bbl. manifold, bolt on your carb and call it good.

Just an FYI, you are aware of the changes you'll have to make to get that 360 roller motor in there, right? i.e. pass. car oil pan/pickup/dipstick (the 273 stuff won't fit the 360), having to modify the pass. side engine bracket and run a spacer on the driver's side between the bracket and engine mount lug, and switching over the timing chain cover and water pump from your 273 onto the 360 (pump inlet changed sides between those years), and re-marking your balancer for the timing marks (which also changed sides when the water pump changed). Or you could get a different radiator with the inlet sides changed instead of changing the TC cover and pump...
And then there's the transmission differences (I assume it's an automatic). The size of the nose on the torque convertor and it's corresponding pocket in the end of the crankshaft changed in '68ish- requiring you to run a reducer bushing in the crankshaft pocket of the later engines in order to fit correctly with the early convertor...
Later 318s would require most of the same mods, except for the motor mounts- those bolt up. You would also be able to use your 273 oil pan if needed.