Swapping an LS Swap?

[Ezzz]

Hey guys, I've been daily driving my 69 C10 with a 4.8 t56 swap for about 4k miles. It's running great but I'm already wishing I had more power. I'm debating between 3 different options and am wondering what has the most carry over from my current set up.

Option 1: LS1 cammed with head work/LS6 cammed with head work if I can get a deal

Option 2: LQ9 cammed with head work

Option 3: Current 4.8 with a turbo setup

Besides how much I can carry over I'm concerned with reliability and fuel efficiency, which I gotta say is a strong suit of my current setup. The t56 with 4.56's and I average just below 20mpg's if I can keep off it (which is why I'm kind of leaning against an LQ9 which would be easiest). I also want to be around 450-500hp/ft lbs at the crank. I figure if I stay around there I don't have to do major upgrades to my trans, rear end, fuel system since that's about what they're rated to.

What do you guys think is my best/cheapest/easiest option?