63 Dodge Dart, now let me see;)

You need 64-66 A-body V8 engine brackets. You'll also want 64-66 A-body V8 steering link. Keep in mind there were a couple changes in the engine compartment starting in 64 to make the V8 fit. The firewall was different where the wiper motor mounts for distributor clearance, and there already a hole for the V8 throttle linkage. The hole in the radiator support was enlarged so a standard V8 22" radiator would fit. Since your donor engine has the later water pump, you either need a later radiator or earlier water pump. Later radiators are somewhat easier to find.