It's called inboarding. There are a few threads around.
"Better" is pretty subjective. I prefer the flexibility of a doubler setup, but I have a feeling you'll have a hard time fitting something that long into an EB. If you like the doubler idea, you might consider using a 4spd (NP435 or T18) with a 203 doubler box into a D20 or 205. I imagine you'd save at least a few inches that way... but I couldn't say for sure.
4500/Atlas is a nice combo, but it's not going to be cheap.