Andreas, It sounds like it's doable
I too would think it would run a bit rich, BUT maybe not low down!!!!
Because the t3 spool up faster and makes more boost low down, than a t3/4....but maybe it's nothing to talk about ???

The turbo I would use should be a t3/4 ar 0.48 to have as little lag as possible. What hp to expect using a 0.48 size t3/4 ???