318 complete combo suggestions...

The 5.2 idea is great IMO only IF he has the money to get another engine and ignore the one he has in the car already. The 5.2 plus OD trans IMO is an excellent idea that can produce a good motivational experience without getting crazy. But yet provide good mileage with that acceleration.

3.55 X .69 = 2.4495 or just simply, a 2.45 final drive ratio. A VERY modest cam change IF desired would be the theme with that final drive ratio, like perhaps a mileage seeking cam (but yet still larger than stock) vs a performance cam.