Truck Dilemma!!!(Long)

[jorgensensc]

Here's the situation:
I'm moving back to Houston next week from California. I live in a suburb called Cypress. My commute to work will be He!!. Gas will end up eating me alive!!! The wife and I were discussing this and I suggested buying a 2500.00 clunker for work and keep the truck. She suggests I sell the truck and get something else better on gas and use the difference and pay off some of our debt. She keeps reminding me how lucky I've been to own the vehicles that I've had, and that most people don't own a truck as nice as this one until they are in their 40s. Please keep in mind she has been supportive of my truck obsession. We just bought a new house and have a daughter. I'm getting out of the military next week (hence the move) and I have to find a good job.
We are not hurting for money, but like most Americans, we are in debt.
How are the new engines for these trucks as far as gas mileage?
I had an LT1 in an S-10 and it was awesome, but this ain't no light S-10. So MPG's from you LT1 guys would be good!! I thought about an LS1, but that will be an expensive swap. What about the newer Vortecs? How are those MPG's in these trucks?? My 350 now gets about 12 mpg's in city and highway driving with a 350 tranny. If I put a 700 tranny, how much better would my mileage be with the overdrive?? I'm just looking for other solutions other than selling my truck.
Obviosley I LOVE my truck and don't want to sell it, and she hasn't said I have to, but I've spent my whole life going against the grain, and the decisions don't just involve me now, they involve my family. I'm just trying to make the best decision here.
What do y'all think??
Sorry for the long post, and thanks for letting me blabber!!