66 dart slant 6 to 360

Radiator, V8 steering centerlink, 360 passenger car oil pan/pickup/dipstick if the 360 came from a truck, Early A cable-type V8 throttle linkage (yours has a throttle rod), the aforementioned kickdown linkages for A body, Early A body v8 exhaust manifolds if you have power steering- headers or late A manifolds and some mods if you don't, conversion kit for the 360 electronic ignition in your '66... If you're going to run dual exhaust, the trans. crossmember needs to be modified; you need to seriously consider a brake upgrade, larger torsion bars, and eventually a rear end- the 7.25 will only take a limited amount of pounding.
Please use the "Search" function- there are TONS of posts on this that will keep you reading for the rest of the week, this gets asked all the time...