The 302 is a well documented swap and should be pretty cheap and easy. Performance parts for that engine are as cheap as you'll find for a carb'ed engine.
The 4.6 will have a lot more fitment issues (mostly the oil filter tries to occupy the same place as the steering box on rangers, and they're so wide that headers can be a pain) as they're the size, long and wide, as a 460. 4.6's are also highly modifiable engines and performance parts are fairly cheap. Modular V8-V10 Blocks (4.6,5.4,6.8, all the same design) can withstand much greater power than the stock 302 block. There will be more wiring involved in this swap.
For a reliable daily driver, I always want fuel injection, because you dont have to spend hours fiddling with a carb every time the weather changes 30 degrees. FI is more reliable as well.
But if it's a race motor, the 302 will be a lot less work and probably easier for you, with a well documented path to follow. But that's not to say a 4.6 won't perform, there's been plenty of super fast 4.6's if you want to go that route.