Assuming they're both Vulcans, the head gaskets are different, upper and lower intake manifolds are different, exhaust manifolds are different, oilpans are different (but I kept the Taurus pan on mine and it fits the 2wd/coil spring chassis nicely YMMV).
If you're switching head gaskets, you'll need to budget for new head bolts as well as they're Torque To Yield and should not be reused.
The timing covers can corrode and leak coolant over time, so I'd inspect them closely and use the best one with all new gaskets.
Also, with any 3.0 swap you need to make sure you have the properly sized fuel injectors. Flex Fuel 3.0s came with 24lb injectors and regular fuel 3.0s came with 19lb injectors. If both engines are flex, then it doesn't matter. If both engines are non-flex, then it doesn't matter. But if one is flex and the other isn't, or you're not sure then it's safest to just reuse the injectors from the Ranger.