I don't think any changes to the induction system will result in a meaningful amount of increased power. It's the equivalent of installing a bigger carburetor on a vintage engine, and it usually didn't make much difference, but could result in a nightmare trying to tune it to work well across the full rev and load range.

The best way to get more top end power is to massage the head.

Those old constant flow mechanical FI systems like Hilborn were very crude. Fuel metering was based on throttle position and pump speed. They worked fine at WOT, high revs once you got the bypass "pill" right, but they couldn't account for VE changes over the full rev range at both WOT and part throttle, so they don't work very well over the speed and load range required for a road engine.

I think you're opening up a real can of worms for yourself. Pull the head, pocket port it and port match to the inlet and exhaust manifolds. If you still want to go further you can probably still find a stroker crank and pistons to make it a 3.2 liter.

Duke