the continuing Mass Air Meter saga

I had a brilliant idea one day to swap the OEM 70mm meter housing to a 80MM housing on my 1995 5.0 keep the same meter. I'm running 24lb injectors and a 75mm TB. It runs ok but has a slight lope at idle. Although it sounds ok and I don't have any drivability issues, other than increased fuel consumption, I prefer it to run right. Any idea if I can run a larger MAFF on this thing without an ECU change? Or is the 95 Cobra ECU swap the more logical thing to do and retain the OEM meter/housing setup?

Thanks!