350 v 454. What's the best option for my situation?

[HunterRotten]

I know there is quite a big difference between 5.7 L of displacement and 7.4 L of displacement. Is the 7.4 L all that much more worth it over the 5.7 L?

My dad and I have now been working on this truck(1978 GMC SWB) almost every weekend and are doing a complete frame-up restomod in our garage with what we have and what's available to us. I currently have the motor my truck came with and a bare block 4 bolt main 350. There's also the fact that my exhaust was made to bolt up to a very nice set of heddman ceramic coated headers for a small block. I don't think accommodating the pipes for a big block is much of an issue but I am out a set of nice headers.

I'm not too worried about gas mileage, this truck is not and probably will not ever be daily driven unless the weather is nice and the humidity is down. I don't see it getting more than 3,500 miles a year if that and I don't think it's going to haul much more than furniture occasionally.

The information given, what would you say would be worth my while for an engine? The current 2 bolt 350, a ground up built 4 bolt 350, or an upgraded 4 bolt 454?

I'm not looking to blow my socks off and be stupid fast, I just want some fun low-end torque and to be able to cruise along like a happy camper.