Change out your needles, easiest thing to do. I was going to say get a bigger fuel pump too, isn't a 350 Buick pump interchangable? A pressure regulator and gauge couldn't hurt either. Check for pressure drop when you squeeze.
Hey, build my dream car. I want a frame from an all wheel drive GMC van and put a GMC Sonoma body on it. They bolt right up. BAM! AWD S-10!