Its a 03 truck, its not that old and the mileage, on the truck as Considered by these days standards , isnt bad.

If moneys tight I would keep it exactly as it is.

The swap, while you have a whole lot of parts, Will cost you a Whole lot more then doing Nothing with the truck as is.

Plus your new MPG will suck and then the unforseen gremlins,$$$ and grief, that will pop up just wont be worth it.

If you had a good income coming in right now I would consider it. But since your laid off, for Now, I would leave well enough alone.

IMO, this is No time, to be doing something like this. Your 03 truck as is, works fine as stated.

Your time, would be better spent in doing side jobs and making a little Extra bucs on the side then doing a old school engine swap on a 03 Dodge 4.7 pickup with all its modern efficiencies.

Thats my honest opinion. mike