The hardest thing to change is the sorry intakes, both n/a and turbo share the double wye design and I'm positive the two inner cylinders get less fuel than the outers. It's hard to change because of the three different water passages, the main tstat flow, the tstat bypass to the carb plenum floor, and the bypass flow to the heater inlet.

I wish I had the fab skills to make up a long tapered tube ram manifold for FI+efi, with a plenum with internal velocity stacks. Long tube to match the undersquare long stroke motor, because long tubes enhance low end torque. You could use a thick flange and what ammounts to plumbing fittings for two water flows (no need for plenum floor heating when you squirt at the back of the intake valve) with a remote thermostat.

I disagree that boring is wasted effort. The ring contact area varies directly with the increase in bore, and the cylinder volume varies by the square of the increase in bore. Mo inches is mo power.

Compression increases also aways mean more power, as long as you stay under the detonation limit of the fuel without having to subtract timing.

It's fairly easy to correct the cam timing to match the head cut, either by using an adjustable cam sprocket or by drilling out the index hole on the stock sprocket and use a bushing with an offset hole.

I betcha Kevin would agree that the most effective mod for a 2.6 is the turbo from a starion. Doubling the hp is easy with only minor mods to the stock starquest system. If you want to play n/a games, I'd start with a 4g64 2.4 swap and get a much more modern engine with 4v per cyl, dohc available, turbo available, mucho aftermarket available, as most of the 2.0 4g63 stuff fits. I think 300 very docile streetable hp is readily available FI, and 150 n/a.