Gary, are you using a VE-based engine management system? The system I use is a simple load vs engine speed look up type system and I knew that I was limited to 60% duty at 6000 rpm because of injector timing restraints so I made a rough fuel map based on injector duty values. I knew I'd need 60% duty at max load and max rpm and then figuring 1-2% duty at idle, I just interpolated between the two points in both axes. Keep in mind that the 60% duty number comes from my planned turbocharged setup and I was starting out naturally aspirated and figured I'd be making about 50% less power n/a versus boosted. When all was said and done, with my fuel map fully tuned and optimized my max duty cycle was 30% so that validated my calcs.
My quicky fuel map was good enough to have the engine start, run, and free rev fairly easily however once I started doing loaded tuning the fuel map changed significantly but it was still a good place to start.
I also used throttle position as my load input with a manifold pressure correction multiplier going on in the background (+100% more fuel for every 100kpa over zero manifold pressure). One assumption I wound up being wrong about was that my throttle body would no longer restrict air flow at about half throttle. In most cases where an over-sized TB is used and basing load on throttle, you generally see a fuel map flatten out above the point where the throttle is no longer a restriction and figuring this would happen around 50%, I flattened my fuel map out between 50% and 100%. Once on the dyno and under load, I found that my throttle never actually "saturated" or reached a point where more throttle position meant no throttle restriction. If anything, I still had a slight amount of vaccum at WOT indicating that my TB wasn't quite big enough (70mm Ford 5.0L TB on a 3.6L four cylinder).