When you use too large a t-body you effectively negate the tuning effects of the intake manifold.
A 65mm is the best size for your engine.
Consider that a Boss 290 has a 75mm t-body and your 5.0 is nowhere near that.

the main reason is gas physically takes up more space, and the larger manifold and internals will come later. and it is only driven on gas and will eventually be dedicated injected gas.

Doesn't matter, If you flood the intake with un-needed air your port velocity will drop and not draw the air/fuel mixture into the cylinder properly. Are you using liquid gas injection?

The 220kw had the 75mm TB

No, the 220 has a 70mm throttle body. The T3 has an 82mm throttle body with a specific manifold.

This is why we need a more comprhensive guide on the 5.0ltr.

sorry, was thinking MAF.

The MAF is 70mm too. Only the 5.6L engine had an 80mm MAF.

Not a very wise mod. 70mm max for this motor

I have an article where throttle body tests were done on a ls1.. Stock throttle body 75mm and manifold were tested against big 90mm throttle body and all sorts of combinations of throttle body/manifold.

To 6500rpm the stock throttle body/manifold (ls6) performed equally with any if the other aftermarket combos. From 6500rpm there were some gains but it was 20hp on 475hp and at 6600rpm+ only. So the motor could breath sufficiently with stock combos.

On a Windsor motor won't see any gains past 70mm due to their low revving nature and heads/manifolds.. All you will do is lose the progressive nature of the throttle, it will be all or nothing performance with 90mm throttle for no extra gains.